Karakteristik Elemen Listrik

Karakteristik Elemen Listrik

Tujuan

-          Menyelidiki suatu hubungan antara Arus dengan Tegangan dari beberapa komponen listrik seperti Resistor, Dioda, dan Semikonduktor.

-          Mengenal bahan-bahan yang dibuat berdasarkan Hukum Ohm

-          Mengetahui prinsip dan cara kerja suatu komponen-komponen Listrik

Teori Awal

Kita tidak dapat mengatakan apa sebenarnya muatan listrik; kita hanya dapat menjelaskan sifat-sifatnya dan perilakunya. Orang Yunani kuno pada tahun 600 sebelum masehi telah menemukan bahwa bila mereka menggosok amber (semacam resin) dengan wol, maka amber itu akan dapat menarik benda-benda lain. Sekarang ini kita mengatakan bahwa amber itu telah mendapat muatan listrik netto, atau menjadi bermuatan. Kata listrik itu sendiri diturunkan dari kata Yunani electron, yang berarti amber. Bila anda menggosokkan sepatu Anda melewati sebuah permadani nilon, Anda menjadi bermuatan listrik, dan Anda dapat member muatan sebuah sisir dengan melewatkannya melalui rambut yang kering.

Salah satu sifat atau karakteristik dari sebuah muatan listrik adalah muatan tersebut dapat bergerak dengan mudah dari satu daerah ke daerah lain dalam medium tertentu. Beberapa bahan yang ada di dunia ini memungkinkan muatan listrik bergerak dengan mudah dalam bahan tersebut. Misalkan sebuah kawat tembaga yang ditopang oleh sebuah batang gelas. Misalkan Anda menyentuhkan satu ujung kawat itu dengan sebuah batang plastic yang bermuatan dan mengikatkan ujung yang lainnya pada sebuah bola logam yang pada mulanya tidak bermuatan; kemudian anda memindahkan batang bermuatan itu dan kawat tersebut. Jika Anda membawa sebuah benda bermuatan lainnya ke dekat bola tersebut maka bola itu akan ditarik atau ditolak. Hal tersebut memperlihatkan bahwa bola tersebut mendapat muatan listrik yang terjadi akibat perpindahan muatan listrik tersebut sehingga bola tersebut menjadi bermuatan.

Kawat itu dinamakan konduktor listrik. Jadi, konduktor adalah bahan yang dapat menghantarkan muatan listrik dengan baik. Nah, jika Anda mengulangi eksperimen tersebut dan anda menggunakan sebuah pita karet sebagai pengganti kawat tersebut, Anda mendapatkan bahwa tidak ada muatan yang berpindah ke pita karet tersebut. Bahan-bahan yang serupa dengan pita karet itu dinamakan dengan Isolator.

Sebagian besar logam adalah konduktor yang baik, sedangkan sebagian besar bahan non-logam adalah isolator. Di dalam logam padat seperti tembaga, satu atau lebih elektron sebelah luar dalam setiap atom menjadi tidak terikat dan dapat bergerak secara bebas di seluruh bahan itu. Gerak elektron bermuatan positif dan inti-inti yang bermuatan positif itu sendiri terikat dalam kedudukan yang hampir tetap di dalam bahan tersebut. Dalam isolator tidak ada, atau sangat sedikit, elektron bebas, dan muatan listrik tidak dapat bergerak secara bebas melalui bahan tersebut. Nah, bahan semikonduktor adalah bahan yang memiliki sifat-sifat di antara sifat konduktor baik dan sifat isolator baik.

Download buku fisika

Bukan bermaksud untuk mempromosikan pembajakan, tapi ini sekedar sharing informasi. Khususnya bagi adik-adik mahasiswa yang mungkin kesulitan untuk beli buku Fisika yang rata-rata ‘mahal’ untuk ukuran kantong mahasiswa (Mahasiswa yg kaya jangan tersinggung ya?).
Berikut ini beberapa alamat untuk mendownload buku fisika langka (khususnya buku fisika asing berbahasa inggris). Nggak bisa bahasa Inggris ? Makanya belajar dong ? masak kalah sama Malaysia !

• www.ebookee.com (cari judul buku fisika pada kolom pencarian, misalnya “fundamental physics”. Anda akan menemukan banyak buku fisika berformat pdf.
• www.esnips.com (cari buku pada kolom search)
• www.teleread.org
• www.learnerstv.com/physics.php
• www.learnerstv.com
• www.motionmountain.net/text.html
• http://e-library.net/Motion-Mountain-The-Adventure-of-Physics__ebooks10272.htm
• www.freebyte.com/free_ebooks/
• http://tutors4you.com/dwnlds.htm
• http://www.physicsforfree.com/
• http://www.onlinecomputerbooks.com/free-physics-books.php
• BEST ENGLISH EDITION (http://khairulhamdi.wordpress.com/2007/06/21/fisdas/)
  

SIAP DOWNLOAD

1. BUKU FISIKA DASAR oleh M. Satriawan UGM Yogyakarta KLIK DI SINI
2. Fisika MESTAKUNG karangan Prof. Yohanes Surya
3. Buku Mathematical Methods for Physics and Engineering 3ed.pdf KLIK DI SINI
4. Classical Mechanics.pdf KLIK DI SINI
5. Principles of Modern Physics.pdf KLIK DI SINI
6. Fundamentals of Physics, Halliday-Resnick KLIK DI SINI atau KLIK DI SINI
7. Solutions of Fundamentals of Physics, Halliday-Resnick KLIK DI SINI
8. Ruhani Physics (Islam and Science).zip KLIK DI SINI
9. Mathematical Tools for Physics.pdf KLIK DI SINI
10. Essential Physics KLIK DI SINI
11. A Course in Fluid Mechanics with Vector Field Theory.pdf KLIK DI SINI
12. The Feynman Complete Lectures on Physics Vol 1, 2, 3 KLIK DI SINI
13. The Feynman Complete Lectures on Physics Vol 2–536 Pages KLIK DI SINI
14. Modern Physics (zip) KLIK DI SINI
15. The Age of Einstein (pdf) KLIK DI SINI
16. Electricity and Magnetism (lebih dari 200 halaman) KLIK DI SINI
17. Conceptual Physics by Crowell
18. Lagrangian and Hamiltonian Mechanics by M.G. Calkin
19. How to solve physics problems (cara menyelesaikan masalah/soal2 fisika)

Reaksi Elementer dan Mekanisme Reaksi

Mekanisme reaksi adalah kumpulan dari beberapa langkah reaksi membentuk reaksi keseluruhan. Kandungan setiap langkah dari mekanisme kesatuan reaksi disebut reaksi elementer, yang terdiri dari beberapa reaksi sederhana. Suatu reaksi elementer menyajikan suatu proses pada tingkat molekul, dapat pula dinyatakan sebagai molekularitas reaksi. Terdiri dari sejumlah spesi terlibat dalam reaksi yang datang, bersamaan membentuk keadaan kritis.

Koordinat reaksi dapt juga disebut sebagai "extent of reaction" [EB Neuman, Chem Reactor Design n Scale Up].
Koordinat reaksi secara umum adalah "nilai mol dari suatu reaktan pembatas pada setiap satu nilai koefisien reaksi".
Nilai koordinat reaksi selalu berubah selama reaksi belum mencapai kesetimbangan.
Apabila suatu reaksi berjalan secara irreversibel, maka dirinya hanya memiliki satu nilai koordinat reaksi (koordinat reaksi pada saat reaksi telah tuntas).

MAri kita lihat definisi berjalan dlm suatu cntoh,
Misalnya ada reaksi A+2B <---> 3C.
Mula2 terdapat 5 mol A dan 5 mol B. Kemudian reaksi tersebut kita selenggarakan..dan misalnya dari koefisien kesetimbangan didapatkan bhw pd kesetimbangan akan terdapat 1mol B.
Mula2 koordinat reaksinya=0 (karena reaksi belum berlangsung),
setelah kesetimbangan tercapai, nilai koordinat reaksinya adalah :

                A    +    2B  <--->  3C
mula          5mol     5mol
Bereaksi    2mol    4mol         6mol
Setimbang 3mol    1mol         6mol

dari perhitungan diatas, nampak bahwa koordinat reaksinya= mol reaktan pembatas / koefisien reaktan pembatas = 4mol / 2 = 2mol 

Kinetika Kimia

Kinetia Kimia adalah bahagian ilmu kimia fisika yang mempelajari laju reaksi kimia, faktor-faktor yang mempengaruhinya serta penjelesan hubungannya terhadap mekanisme reaksi.Dalam kimia fisik, kinetika kimia atau kinetika reaksi mempelajari laju reaksi dalam suatu reaksi kimia. Analisis terhadap pengaruh berbagai kondisi reaksi terhadap laju reaksi memberikan informasi mengenai mekanisme reaksi dan keadaan transisi dari suatu reaksi kimia. Pada tahun 1864, Peter Waage merintis pengembangan kinetika kimia dengan memformulasikan hukum aksi massa, yang menyatakan bahwa kecepatan suatu reaksi kimia proporsional dengan kuantitas zat yang bereaksi.

Kinetika kimia disebut juga dengan istilah dinamika kimia yang diakibatkan karena adanya gerakan molekul-molekul, elemen atau ion dalam mekanisme reaksi dan laju reaksi sebagai fungsi waktu.


Persamaan Arrhenius memberikan nilai dasar dari hubungan antara energi aktivasi dengan rate proses reaksi. Dari Persamaan Arrhenius ini , energi aktivasi dapat dinyatakan sebagai berikut :

Di dalam ilmu kimia, energi aktivasi merupakan sebuah istilah yang diperkenalkan oleh Svante Arrhenius, yang didefinisikan sebagai energi yang harus dilampaui agar reaksi kimia dapat terjadi. Energi aktivasi bisa juga diartikan sebagai energi minimum yang dibutuhkan agar reaksi kimia tertentu dapat terjadi. Energi aktivasi sebuah reaksi biasanya dilambangkan sebagai E_a, dengan satuan kilo joule per mol (KJ/mol).

Terkadang suatu reaksi kimia membutuhkan energi aktivasi yang teramat sangat besar, maka dari itu dibutuhkan suatu katalis agar reaksi dapat berlangsung dengan pasokan energi yang lebih rendah.

Reaksi kimia adalah suatu proses alam yang selalu menghasilkan antarubahan senyawa kimia. Senyawa ataupun senyawa-senyawa awal yang terlibat dalam reaksi disebut sebagai reaktan. Reaksi kimia biasanya dikarakterisasikan dengan perubahan kimiawi, dan akan menghasilkan satu atau lebih produk yang biasanya memiliki ciri-ciri yang berbeda dari reaktan. Secara klasik, reaksi kimia melibatkan perubahan yang melibatkan pergerakan elektron dalam pembentukan dan pemutusan ikatan kimia, walaupun pada dasarnya konsep umum reaksi kimia juga dapat diterapkan pada transformasi partikel-partikel elementer seperti pada reaksi nuklir.
Reaksi-reaksi kimia yang berbeda digunakan bersama dalam sintesis kimia untuk menghasilkan produk senyawa yang diinginkan. Dalam biokimia, sederet reaksi kimia yang dikatalisis oleh enzim membentuk lintasan metabolisme, di mana sintesis dan dekomposisi yang biasanya tidak mungkin terjadi di dalam sel dilakukan.

Jenis-jenis reaksi
Beragamnya reaksi-reaksi kimia dan pendekatan-pendekatan yang dilakukan dalam mempelajarinya mengakibatkan banyaknya cara untuk mengklasifikasikan reaksi-reaksi tersebut, yang sering kali tumpang tindih. Di bawah ini adalah contoh-contoh klasifikasi reaksi kimia yang biasanya digunakan.

• Isomerisasi, yang mana senyawa kimia menjalani penataan ulang struktur tanpa perubahan pada kompoasisi atomnya
• Kombinasi langsung atau sintesis, yang mana dua atau lebih unsur atau senyawa kimia bersatu membentuk produk kompleks:

N₂ + 3 H₂ → 2 NH₃

• Dekomposisi kimiawi atau analisis, yang mana suatu senyawa diurai menjadi senyawa yang lebih kecil:

2 H₂O → 2 H₂ + O₂

• Penggantian tunggal atau substitusi, dikarakterisasikan oleh suatu unsur digantikan oleh unsur lain yang lebih reaktif:

2 Na(s) + 2 HCl(aq) → 2 NaCl(aq) + H₂(g)

• Metatesis atau Reaksi penggantian ganda, yang mana dua senyawa saling berganti ion atau ikatan untuk membentuk senyawa yang berbeda:

NaCl(aq) + AgNO₃(aq) → NaNO₃(aq) + AgCl(s)

• Reaksi asam basa, secara luas merupakan reaksi antara asam dengan basa. Ia memiliki berbagai definisi tergantung pada konsep asam basa yang digunakan. Beberapa definisi yang paling umum adalah:
  • Definisi Arrhenius: asam berdisosiasi dalam air melepaskan ion H₃O⁺; basa berdisosiasi dalam air melepaskan ion OH^-.
  • Definisi Brønsted-Lowry: Asam adalah pendonor proton (H⁺) donors; basa adalah penerima (akseptor) proton. Melingkupi definisi Arrhenius.
  • Definisi Lewis: Asam adalah akseptor pasangan elektron; basa adalah pendonor pasangan elektron. Definisi ini melingkupi definisi Brønsted-Lowry.
• Reaksi redoks, yang mana terjadi perubahan pada bilangan oksidasi atom senyawa yang bereaksi. Reaksi ini dapat diinterpretasikan sebagai transfer elektron. Contoh reaksi redoks adalah:

2 S₂O₃²⁻(aq) + I₂(aq) → S₄O₆²⁻(aq) + 2 I⁻(aq)

Yang mana I₂ direduksi menjadi I^- dan S₂O₃^2- (anion tiosulfat) dioksidasi menjadi S₄O₆^2-.

• Pembakaran, adalah sejenis reaksi redoks yang mana bahan-bahan yang dapat terbakar bergabung dengan unsur-unsur oksidator, biasanya oksigen, untuk menghasilkan panas dan membentuk produk yang teroksidasi. Istilah pembakaran biasanya digunakan untuk merujuk hanya pada oksidasi skala besar pada keseluruhan molekul. Oksidasi terkontrol hanya pada satu gugus fungsi tunggal tidak termasuk dalam proses pembakaran.

C₁₀H₈+ 12 O₂ → 10 CO₂ + 4 H₂O

CH₂S + 6 F₂ → CF₄ + 2 HF + SF₆

• Disproporsionasi, dengan satu reaktan membentuk dua jenis produk yang berbeda hanya pada keadaan oksidasinya.

2 Sn²⁺ → Sn + Sn⁴⁺

• Reaksi organik, melingkupi berbagai jenis reaksi yang melibatkan senyawa-senyawa yang memiliki karbon sebagai unsur utamanya.

Sedangkan dari itu semua dikenal
Laju reaksi suatu reaksi kimia merupakan pengukuran bagaimana konsentrasi ataupun tekanan zat-zat yang terlibat dalam reaksi berubah seiring dengan berjalannya waktu. Analisis laju reaksi sangatlah penting dan memiliki banyak kegunaan, misalnya dalam teknik kimia dan kajian kesetimbangan kimia. Laju reaksi secara mendasar tergantung pada:

• Konsentrasi reaktan, yang biasanya membuat reaksi berjalan dengan lebih cepat apabila konsentrasinya dinaikkan. Hal ini diakibatkan karena peningkatan pertumbukan atom per satuan waktu,
• Luas permukaan yang tersedia bagi reaktan untuk saling berinteraksi, terutama reaktan padat dalam sistem heterogen. Luas permukaan yang besar akan meningkatkan laju reaksi.
• Tekanan, dengan meningkatkan tekanan, kita menurunkan volume antar molekul sehingga akan meningkatkan frekuensi tumbukan molekul.
• Energi aktivasi, yang didefinisikan sebagai jumlah energi yang diperlukan untuk membuat reaksi bermulai dan berjalan secara spontan. Energi aktivasi yang lebih tinggi mengimplikasikan bahwa reaktan memerlukan lebih banyak energi untuk memulai reaksi daripada reaksi yang berenergi aktivasi lebih rendah.
• Temperatur, yang meningkatkan laju reaksi apabila dinaikkan, hal ini dikarenakan temperatur yang tinggi meningkatkan energi molekul, sehingga meningkatkan tumbukan antar molekul per satuan waktu.
• Keberadaan ataupun ketiadaan katalis. Katalis adalah zat yang mengubah lintasan (mekanisme) suatu reaksi dan akan meningkatkan laju reaksi dengan menurunkan energi aktivasi yang diperlukan agar reaksi dapat berjalan. Katalis tidak dikonsumsi ataupun berubah selama reaksi, sehingga ia dapat digunakan kembali.
• Untuk beberapa reaksi, keberadaan radiasi elektromagnetik, utamanya ultraviolet, diperlukan untuk memutuskan ikatan yang diperlukan agar reaksi dapat bermulai. Hal ini utamanya terjadi pada reaksi yang melibatkan radikal.

Laju reaksi berhubungan dengan konsentrasi zat-zat yang terlibat dalam reaksi. Hubungan ini ditentukan oleh persamaan laju tiap-tiap reaksi. Perlu diperhatikan bahwa beberapa reaksi memiliki kelajuan yang tidak tergantung pada konsentrasi reaksi. Hal ini disebut sebagai reaksi orde nol.

Moving in line with technology

The presence of a technology is often accompanied by the emergence of news things too, whether to complement or provide another choice to consumers. Just look at when Microsoft launched its Windows 7 operating system, which was then followed by the launch of a number of devices supporting the latest hardware in the form of a keyboard, mouse, and web cam. Windows 7 promises a more pleasant experience in multi-user, such as a more innovative touch screen to navigate the system. 

The device offered by Microsoft in its latest breakthrough is the Wireless Comfort Desktop 5000, Bluetooth Mobile Keyboard, Life Cam Cinema, and the Wireless Mobile Mouse 4000. Overall it was an innovative product that is supported by Windows 7. Wireless Comfort Desktop 5000 is a keyboard and mouse combo that has a Task bar button, a new feature that allows users to navigate quickly through several windows in windows 7. 

Bluetooth Mobile Keyboard 6000 is the thinnest keyboard owned by Microsoft. This new keyboard has a unique form of ergonomic design. Life Cam Cinema became the first web cam equipped with 720p high-definition quality and low light performance of the slick. While the Wireless Mobile Mouse 4000 is a mouse that is equipped with technology that has been manufactured like Blue track and sold at affordable prices.

Repaint your Wall in House

Usually in Indonesia people, in Ramadhan, people prepare them house to face Idul Fitri day. One of habits that Indonesia people do is repaint wall on their house and make the house beautiful. When we see people paint the house, we think that it is easy to do. But, the truth is there are plenty step to do paint and get better result. Here the step you have to do

• Before you repaint your wall, you have to know the condition your wall on your house. The conditions are good or not good. It will influent your paint, because the paint it depends on the situation. Wall with condition if there is not has mushroom, lime kiln limepot.
• On good condition, the wall surface only being cleaned from dust or oil. If you do not clean the dust, your wall will have a black flack.
• The next step is paint a sealer (basic paint) which became a connection between the old paint and the new paint. On this sealer, the new paint it will be easy to stick with the old paint. After the sealer paint on the wall, wait for 3 hours until the paint dry.
• And then, the new paint is coming. Give 3 or 4 times paint to get good result and give a few hours, maybe 3-4 hours and give another paint.

The concept of evolution in biology

In 1858 a biologist named Charles Darwin (1809-1882) gave a lecture sponsored by the Linnean Society in London, and a year later was published his book The Origin of Species in 1859. Establishment posed in lecture and the book is that all forms and types of creatures that live there now exist in the world, with affected by various natural processes, evolve or grow very slowly from the forms is very simple, one-celled creature into several new, more complex types. New types of creatures, each also evolved into new species into an increasingly complex, so that takes a very long time. But who knows in the 1700s the development of biological sciences in Europe and America in fact dominated by science theory of natural theology. This is precisely contrary to the concept of the theory proposed by Charles Darwin. Broadly speaking, scientific theories of natural theology is a philosophy which aims to discover God's plan by studying nature, so do the classification of species of natural theology to express the level of the scale of life created by god.

Carolus Linnaeus (1707-1778) that we know as the father of taxonomy. Linnaeus developed the binomial system (the system of classification of living things) that are still used today for the naming of organism on the basis of genus and species. Linnaeus also adopted a system for classifying similar species into a particular category of tiered levels. So that for Linnaeus, grouping similar species together showed no evolution of a relationship. Back to the concept of Darwinian evolution, the laity in western Europe initially very opposed to this establishment, and although already there are numerous papers on the historical process of evolution of human society at the time , but the idea of evolution of living species can not be accepted. That's because in the mid-19th century in Europe there is a generation and re-tightening of religious life, and ideas like the idea that Darwin considered the ideas that conflict with the infidel religious belief which says that all kinds of creatures in the world (including human ), is the result of God's creation are absolute. Except that the idea that humans and apes are descended from a creature the same, even that man is a monkey, an idea that is too difficult for lay people to accept.

In addition there is also Charles Darwin's other biologists, namely A. Wallace (1823-1913), independently of Darwin had developed the idea of evolution beings in the same world, although more expanded Wallace about the process of natural selection in determining the physical form of a new species in the evolutionary process. Darwinian natural selection, only mention about it in passing and in his lecture. Basically there is no difference between theory concerning the processes of biological evolution from these two experts and both are of the opinion that among the individuals within one species there is always a small difference. Some individuals are vulnerable less able to withstand the pressures of nature, and off, whereas individuals who are stronger can survive and live straight, gave birth to offspring and pass on their properties had been strong for some of his descendants. In the next generation of this process over and over again, and so on. According to Wallace, the more cruel and harsh natural pressure, the higher the quality is a requirement for an individual organism within a species at a certain generation, and if the natural state of change, then only individuals of a species that has the properties can survive to live. And this is by Darwin and Wallace have called "natural selection".

How to Overcome Natural Acne

Natural remedies just as effective as medication in dealing with acne. In fact, the possibility of better and more powerful. Sometimes, it takes the body is balanced nutritional care and proper body. Healthy with natural ways are the steps very well for the achievement of useful life. Similarly, in conducting special body treatments, among others concerning the proper skin care and especially about acne. Here, the natural treatment recommended

Use of honey

Of course everyone has to know this food, in addition to good for the health of honey is also beneficial for our skin care, especially regarding facial treatments. According to research, honey contains antibacterial compounds so good for disinfecting and healing minor acne on the face. In addition, gentle for sensitive skin. Apply honey to the face (such as wearing a face mask) with regularly. Do it regularly, with one or two times a week
Cleaning Face on a regular basis

Perform facials to cleanse the face with acne soap as much as two times a day. Wash the face with a sulfur based soap formulated for acne. First when we wake up and try to do as well as gently as possible and before bed. Cleaning the skin is excessive force sebaceous glands to produce more sebum which has the potential to improve acne in face


Drink Multivitamins

Acne on the face may member sign that there was something wrong in the skin because we know the skin is also dependent on the nutrients that we consume. Skin is also an important organ that is often overlooked. If you do not receive proper nutrition, your body will fight back. One way is to insurgency skin with excessive sebum produced so clog the pores on facial skin and reduces the skin's ability to resist against bacteria that exist and this may have potential in acne

Eating Carrots

Carrots contain beta carotene fibers are also included in vitamin A. Vitamin A strengthens the protective tissue and skin to prevent acne and help reduce sebum in the skin. Vitamin A is also important to maintain and repair the skin and tissue that build the mucous membrane. Vitamin A is also a powerful antioxidant that is required to remove body toxins

Avoid Makeup

Pressed in the skin of makeup products can cause the pores on the face of congestion, create more pimples and blackhead. If you must wear makeup, use cosmetics, which is basically water, not with oil-based materials

Consumption of Zinc

Zinc is antibacterial compounds and essential elements in the glands that produce oil for the skin. Low dietary zinc can cause acne on the face

Keep hair off our face

If you cut bangs hair long, then lift your bangs to stay away from your face. Hair also contains oil and when exposed to direct contact with the skin of the face, it was likely that the oils from the hair will stick to the skin so that the potential of acne on the face

Implementation of a good experiment

In accordance with some experiments that we often do both at the school and even at university level, we can set up several questions that should be considered in conducting an experiment. Practicum course at the university in the state of the system which does not always allow us to focus on the experiment.

Therefore, to conduct a good experiment needs to be seen a number of factors, among others

1. Repeating the experiment in the same circumstances
   With this road soon becomes obvious errors that arise due to miscalculation in the experiment and other oversight. Also with the repetition several times can be reduced due to effects such a random error in reaction time, for example in the use of a stopwatch
2. Repeat using other measuring devices
   If a meter is damaged or suspected of the situation is less precise, clear way to handle it is to replace these tools with other tools. In normal practice, if the experiment goes well, students do not have to think about this problem. But lab officials should check all equipment regularly
3. Doing a comparison with the equipment under other circumstances. If there is suspicion that a formula or theory is incompatible with the existing experimental results, may place the necessary changes
4. Comply with practical instructions in the use of tools
   Ie, before a device is used, its use should be studied first go through this guide so that the usage will be more effective and the existing experimental equipment can be prevented from the defects that we want and besides that can prevent us from dangers that might occur due to errors in using experimental tool

Anatomical Sciences and Problems of human multicolored

Anatomical sciences in the period between the 16Th century and the 19Th is a science that is certainly involved in the problem or mono genesis poly genesis human beings, and therefore also put big attention to ethnographic material and ethnographic at that time. Actually, since the time classical Greek philosophers such as Herodotus (circa 450 BC). Hippocrates (circa 400 BC), but especially Aristotle (circa 350 BC), who have all had to pay attention also to the science of human anatomy, have often used the skulls from neighboring nations who comes from the Greek-race other races, as comparative material in the study of anatomy.

Comparative studies of anatomy has become more intense, especially after the Europeans see more multi-colors of human physical traits, and after more and more appear essay containing ethnographic material as well as reports on the physical characteristics of different-colored people after the 16th century. An example of a similar study of comparative anatomy is such research conducted by physician Andreas Vesalius (1514-1564) of Spain and by physician and concurrent biologist and physiologist Carlos Linnaeus (1707-1778) of Sweden, as well as by a biologist and physiologist George de Buffon (1707-1788) from France.

The analysis and classification of multi-color features of the human body is widely based on information materials contained in the articles of ethnography, was carried out by JF Blumenbach, physiology and anatomy expert (1752-1842). In his book De Humani Generi Verietate (1779), which has the meaning of "Know the Origin of Human beings Aneka-Color" can be said was born of a science of physical anthropology as a new science. When it arises also concepts such as races Caucasian, Mongolian, Ethiopian, American and Malays, which is mainly based on skull characteristics, and about starting the beginning of the 19th century that most of the major universities in Europe present lectures in the science of physical anthropology. In the mid-19th century appear the names of characters such as PP Broca physical anthropology from France, R. Virchow from Germany, G. Sergi from Italy, which has members contribute greatly to the further development of the science of physical anthropology.

Classification of multi-color features of the human body in relation to the history persebarannya on earth, performed by a doctor named JC Prichard who lived from 1786 until 1848. He linking ethnographic data about the physical characteristics of the Tada ethnography of various peoples culture spread in the world. A theory which states that changes in the way of life, it means a change of culture, is also one cause of changes in human physical traits, developed and diuraikannya in two important works, namely Researches into the Physical History of Man, published in 1813 and The Natural History of Man in 1848. Both works are generally regarded as the beginning of the science of physical anthropology, taught at universities in Europe as a science in itself, separated from the science of anatomy.

Role of Graphs in the practicum

Graphs are often used in scientific literature because it can directly show the relationship between two quantities, and more important information more easily captured visually from the graph and the data listed in table form. Besides the role as the above graph, the graph also has a role in analyzing data and testing the model at the time of execution of the experiment.

The graphics are most often used is a Cartesian graph, which has an axis perpendicular to the cross, and fixed or linear scales on each axis. The simplest is a coordinate system in which both axes using the same scale and this is often used by people to draw a mathematical formulas. However, in most applications experimentally, the two quantities are about to be drawn in graphical form different from each other and the scale also have different things. A pair of data, such as Xo and Yo, respectively, can be placed on the graph area in accordance with the scale for x and y axis respectively.

In addition to Cartesian graph, some form of graphs that are commonly used in certain situations are polar graphs, and charts logarithmic graph consisting of log-linear (semi log) and log-log graph. In all types of graphs mentioned above, every point in the graph represents a particular data set, and vice verse. The histogram is a kind of graph that is often used in statistical analysis. Histogram showing the number of members or events that fall between certain values in the observable quantities. Need we know that basically the graph shows the relationship between two quantities, but the effects of other values which can be shown by putting a few curves, namely the value of the third scale different. But this way there is no scale for the magnitude of the third. Another way is to use three-dimensional graph that resembles the map arise, but the paint is very difficult and usually done with a special graphics program on the computer.

Buku Elektronik Mekanika Quantum

• Judul : Quantum Mechanics (A Modern Development)
• Penulis : Leslie E. Ballentine
• Silahkan Download buku di atas disini

Tetrameter

One chemical called Tetrameter examination, ie examination of the number of substances which are based on measuring the volume of the reaction solution needed to react stoichiometrically with substances that have been determined. Tetrameter or volumetric analysis is one method of checking a large number of chemical usage. This is due to several reasons. On the one hand, this way is profitable because its implementation is easy and fast, precision and accuracy is high enough. On the other hand, how does this benefit because it can be used to determine levels of various substances to which have different properties. Basically this means Tetrameter consists of measuring the volume of the reaction solution needed to react stoichiometrically with the substance to be determined. Reagent solution was usually known concentration with certainty, and called pen titer or standard solution. While the process of adding pen titer into solution substances that will be determined is called titration. In the process section by section pen titer added to a solution of substances to be determined with the aid of a tool called the Biuret so as to achieve equivalence point.

Equivalence point is the point at the specified reagents and substances react stoichiometrically perfect. Titration should be discontinued on or near the point of this equivalence. The total volume of unused pen titer to reach the point of equality is called the volume pen titer equality. By knowing the volume of equality, pen titer concentration and stoichiometric factor, then the number of prescribed substances can be calculated easily. Around the point of equality, as a result of interaction between substances that are determined by pen titer, system properties change sharply, the properties that changed it certainly can be a fiber optic, chemical, or electrochemical properties. Changes in these properties can be used to specify the location of the equivalence point.

Very often analyzed substantially with the addition of solution of known concentration and the reaction took place quantitatively at substantially this analysis. If possible mix volume added into the solution reacts with all the analysis substance sufficient in the sample, and then the sample concentration can be calculated. Analysis of this kind, where the critical mixture of volume is needed when analyzing, classified as volumetric analysis. The process by which solutions of known concentration is added to the solution of known concentration will be referred to as a titration process. Knowledge of the solution is very important because the greater the chemical and biological reactions occur in the form of liquids, especially in the form of a solution with solvent water. Solution can be defined by a homogeny system consisting of two or more components. The terms solvent and solute could actually exchanged, but the term usually used for liquid solvent, if the solution consists of the solids in the liquid or gas. This term for other types of solutions commonly used to express the substance contained in a larger quantity. Components are much less common is called the solute.

All gases can be mixed with each other. Therefore, all the gas mixture is a solution. Liquids in general can dissolve a variety of other liquids solids and gases can form a solution. When the solvent water, the solution formed is known as a solvent solution with water. Condensation is formed when the gases, liquids or other solids dissolved in solution. Solid solution is not very important in biological systems, but it is very important in metallurgy.

Partial molal volume

Knowledge of the solution is very important, because the greater the chemical and biological reactions that occur in the form of liquids, especially in the form of a solution with solvent water. Solution can be defined as a homogeneous system which consists of two components or more substances. The term of solvents and solutes can actually exchanged, but the term usually used for liquid solvent, when the solution consists of solids or gases in liquids. This term for other types of solutions commonly used to express the substance contained in a larger quantity. Components are much less common is called the solute. All of the gas can be mixed with each other. Therefore, all the gas mixture is a solution. Liquids in general can dissolve a variety of solids, other liquids, and gases can form a solution. When the solvent water, the solution formed is known as a solvent solution with water. Solid solution is formed when gases, liquids or other solids dissolved in solution. Solid solution is not very important in biological systems, but it is very important in metallurgy.

Not all systems have a simple properties like the binary system. Some systems during the fractional distillation can only produce a pure component alone. The rest was a mixture that has a fixed boiling point. One example of a mixture that produces the minimum boiling point of ethanol-water system. In such a system, not pure alcohol may be produced by fractional distillation. When several substances are mixed together, the total volume of the mixture is generally different from the total volume of individual components. Or contraction of the reaction force between molecules intermolecular intermolecular emerged from a mixture of styles between the molecules, and very real when the two substances is the solution. Rate of change of the volume described quantitatively in the partial molal volume of formula from.

In the experiment we measure the partial molal volume of ethanol in water at different concentrations. Partial molal volume is very effective for calculating the volume of one mole of ethanol in concentrated solution, which differs from the volume of one mole of pure ethanol. A very common method is to calculate the precise mass of the known volume of a solution computed on a calibrated glass vessel called piknometer. Piknometer quite difficult to use, even then, and in this experiment, we can calculate the density of a known solution with sinker - quartz stone weights tied to the arms of chemical equilibrium, which is immersed in solution (Matthews, P. 1985) Solvents used in chemical examination of not only water, but can also nirair solvent (not water). The role of solvent-solvent will be described in detail in this chapter. This description begins with an explanation of the solvent properties of water and solvent properties nirair, followed by a discussion of the interplay of solvent-solvent and mutual influence between ions in the solvent. At the end of this chapter discussed the role of solution ionic strength in influencing chemical equilibrium, which in turn will affect the chemical examination.

Blackbody radiation

Sun rays coming to Earth, carrying thermal energy (heat) through electromagnetic waves. Heat transfer is called radiation, which can take place in a vacuum. Radiation emitted by an object as a result of its temperature is called heat radiation. Obviously, every object is continuously emitting heat radiation in the form of electromagnetic waves. In fact, a cube of ice that we often see in everyday life also emit heat radiation energy, although with a very small fraction of this heat radiation in the visible light region.

In the laboratory, newly visible objects radiate heat if the temperature exceeds 1000 K. At this temperature the object started glowing red just like when we turn on an electric stove coil and color indicates the color red. When the temperature rose to 2000 K, the object will be fluorescent yellow or whitish like the fluorescent iron on the light bulb. So also the higher the temperature of the object will be more different colors are emitted. However, in the physical sciences, there is a hot body that emits thermal spectra with the same characters / universal. Black body (black body) is the name of the object. In physics itself, a black body is an object that absorbs all electromagnetic radiation that falls to the black body. No radiation can exit or reflected by the black body.

In the experiment, the object that most closely approximates a black body radiation is the radiation from a small hole in a cavity. Any light entering the hole close and this will be reflected and the energy absorbed by the walls of the cavity many times, regardless of wall material and the wavelength of incoming radiation (long wavelength smaller than the diameter entrance hole). This hole is the approach of a black body. Although his name black object, he should not really black because he also can transmit energy. The number and types of electromagnetic radiation emitted depends on the black body temperature. Black body with a temperature below 700 K almost all the energy emitted in the form of infrared waves, very little in the visible wavelengths. The higher the temperature, the more energy is emitted in the visible wavelength starts red, yellow, orange and white.

The higher the temperature when the cavity is heated, the more visible light can be seen. The observed waves could not be explained by classical electromagnetic theory and statistical mechanics. This theory predicts a high intensity at low wavelengths (ie high frequency). Theoretic Problem was solved by the Max Planck stated that electromagnetic radiation propagating in empty space is not continuous but propagate in the form of packages or often called a photon. While the term black body itself was first introduced by Gustav Robert Kirchoff in the year 1862 and the radiation that comes out / is emitted by a black body that is called blackbody radiation.

Perubahan Energi

Sebuah benda yang memiliki gerak dan berada pada ketinggian tertentu memiliki sebuah Energi. Jika ditinjau dari segi gerak benda tersebut maka benda tersebut memilki Energi Kinetik sedangkan benda yang berada dalam suatu ketinggian maka benda tersebut memilki Energi berupa Energi Potensial yang dapat ditinjau dari massa, ketinggian benda tersebut.

Energi suatu benda atau sistem adalah kemampuan benda atau sistem itu melakukan kerja. Tiap perubahan baik kimia maupun fisika, melibatkan perubahan energi. Energi mempunyai berbagai bentuk, energi panas atau kalor, energi listrik, energi radiasi, energi kimia dan energi nuklir merupakan sebagian kecil dari energi yang ada.

Dari penjelasan itu semua, semua energi tersebut datang bukan karena dibuat oleh sesorang atau akibat perlakuan seseorang. Maka, ada sebuah Hukum Kekekalan Energi, yakni “Energi tidak dapat diciptakan dan tidak dapat dimusnahkan, hanya dapat di ubah ke bentuk energi yang lain”. Berikut penjelasan dari beberapa energi yang sering dikenal.

Energi Listrik
Energi Listrik adalah macam energi yang dikaitkan dengan lewat sebuah atau suatu arus listrik. Energi listrik diubah menjadi energi cahaya dalam sebuah lampu listrik, menjadi energi panas dalam suatu kompor listrik menjadi energi mekanika dalam sebuah starter sebuah mobil.

Energi Radiasi (Radiant Energy)
Energi Radiasi merupakan energi yang dikaitkan dengan cahaya biasa, sinar-X, gelombang radio dan sinar infra-merah. Energi radiasi juga disebut radiasi elektromagnetik. Semua radiasi semacam ini merambat dalam ruang dengan kecepatan cahaya sebesar 3×〖10〗^8 m⁄s.

Energi Kimia
Energi Kimia adalah energi yang dimiliki suatu zat karena keadaan kimia suatu bahan. Energi kimia diubah menjadi energi semacam lain bila materi mengalami perubahan denang macam yang sesuai. Contoh, batubara dan bensin yang terbakar, atau bila makanan yang kita makan terbakar dalam sel-sel kita. Suatu energi kimia diubah menjadi energi panas. Kebalikannya semua macam energi dapat diubah menjadi energi kimia oleh suatu perubahan yang sesuai macam. Energi radiasi dari matahari diubah menjadi energi kimia dalam suatu pohon jagung yang sedang tumbuh; energi kimia itu dikaitkan dengan zat-zat yang membentuk tongkol. Energi kimia merupakan sumber utama energi untuk pabrik, perumahan dan transportasi.

Energi Nuklir
Energi Nuklir atau energi atom sering dikaitkan dengan cara-cara atom itu disusun. Metoda-metoda untuk mengubah energi semacam ini menjadi energi panas, cahaya dan bentuk lain yang telah dikembangkan sejak tahun 1941. Sebenarnya semua bentuk energi dapat dikelompokkan dalam dua kelas umum: energi potensial dan energi kinetik. Hal ini merupakan komponen dasar dari energi kinetik.

Energi Kinetik
Energi Kinetik adalah sebuah energi dari suatu benda karena gerakan karena benda tersebut. Pada saat air mengalir lewat turbin, per arloji perlahan-lahan mengendor, atau bensin terbakar dalam mesin mobil, energi potensial diubah menjadi energi kinetic. Suatu mobil yang bergerak, bola yang sedang melambung, pesawat yang sedang terbang dan semua memiliki energi kinetik.

Transformer

In the inductance, as we all know that a changing current produces a magnetic flux induces a voltage change into a coil. In this case the influence of a magnetic flux is changing and is owned by two or more different coils. Coil-coil adjacent took part called a flux along with the coupling together (mutually coupled). In circuits that have a trailer together, a stream that changes in one roll of electrical current in the coil produces voltage other scrolls in a trailer with it. Voltage electrical current is characterized by a mutual inductance (mutual inductance) contained between the coil-coil adjacent to each other. Inductance which together were not we think of as an element in a basic circuit because as we find out earlier, is always possible that these existing inductance representing the influence of mutual inductance, in a series with an equivalent circuit containing self inductance of the voltage sources and existing flows. A coil-coil system is arranged in connection with which rolled on a core called a transformer. Transformers are available in various types and sizes. In a radio receiver, television, and stereo equipment are often used to connect the various levels of reinforcement in the system. Transformer is used to raise or lower the voltage and to adjust the level of impedance in a power system and electronics. In a linear transformation, ie a transformer which consists of a coil-coil are linear, self inductance and mutual inductance is the combined properties of these linear transformations. Furthermore, we can find in a transformer has a store of energy and the properties associated with the impedance. Especially in the area of existing frequencies in the linear transformation, the frequency is very important because in every application of the transformer has an alternating current which is in a state fixed. Taken from the book with the title of Authorship Budiono Mismail Circuit. Published by Institute of Brawijaya University Publishing in August 29, 1981 Second Edition Volume One.

Ions Concept

The concept of the ion is a continuation of the continuous substances by the effects of Debye falkennegan wylen and alex, who lives on the circumstances. E = 10 ^ 5 v / cm. In this accretion is the result of the conductivity was observed (effect of Warren). In this accretion conductivity results from the fact that limited time (time off) is a form of pressure. Something about the atmosphere to form ions. In fact high, very fast exchange with the resulting loss at atmospheric pressure. Atmosphere did not have time to form and also can not slow down the ions. The result of this asymmetry is not visible and the conductivity are increase. For the same reason the addition of conductivity at high frequencies around 3 x 10 ^ 6 cms (dybye effects) / falkennegan. The transition ions on the instructions that it should have a very difficult motion at atmospheric pressure that can not be measured and will follow the movements of atoms are very difficult at atmospheric pressure and an increase conciliates. At high frequencies of both could be asymmetrical electropothic no results.

Molar conductivity of electrolyte, does not depend on the concentration of K appropriate if compared with the concentration of electrolytes. However, in practice, the molar conductivity berparsial against concentration. One reason is the number of ions in solution may not contain or proportional to the concentration of electrolytes. For example, the concentration of ions in weak acid solution depends on the acid concentration is complicated, and alloys that make up the concentration of the acid. Do not make double the existing number of ions. Both because the ions interact more strongly. Then the conductivity can not be proportional to the number of ions available. Measurement of the concentration dependence of molar conductivity showed the existence of two classes of electrolytes. General properties of the molar conductivity of electrolyte strength is only slightly decreases with increasing concentration. General properties of a weak electrolyte solution is a tool of the normal conductivity when the concentration approached or declined sharply to low values when the concentration increases. This classification depends on the solute and solvent used, for example lithium chloride which is a strong electrolyte in water. Strong electrolyte is a substance that perfect ionized in solution and includes ions.

Hernia

Actually, how crucial that Hernia injury for Football players? Andriy Shevchenko clearly gave prove when he was playing for Chelsea in Barclays Premiere League.

Well, Hernia could mean there is a more stretch on a part of man sex which effecting a big lumps. This big lump is disturbing testis part. Which means, when the football players run to kick the ball, the lump will be fell so hurt. In Football, this injury caused by a too much stretch when kicked the ball, run, turn the body and jumping.

Football became the first caused of this injury. In football, there are 2 kinds of Hernia injury i.e. inguinal hernia and Gilmore`s groin (usually well known as sports hernia).

If hernia could not heal on surgeon process, surely the person could be hard to do his daily activity. Not only play football but also like up and down from the bed, driving the car. A pain on part of man sex could very hurt when the age of the football player up. The suspect could be fell usual if this injury happened for a long time but if the injury not be healed, could be the injury become more complex than before.

For football players, they always wonder how to prevent this injury?

of course core strength and core stamina training on field surely complete your exercise for muscle strength on your vital parts. Core strength well known as a training of muscle strength on the center of your vital parts with using stretch tools of thigh and legs muscle and core stability is a training on your stability.

The strength not only on legs muscle which stand the vital parts, but also on shoulder structure and the parts of up body could be give an stability. So, the train process and warming up process for football players clearly became the most important things for their condition keep stable. The portion of training also has an influent for this injury.

Stages of cell division

Inter phase. At the stage of inter phase, the cell is considered a rest from division process. However, the actual stage of the inter phase is an active and important step to prepare the division. Preparation of DNA replication (doubling the DNA from one copy into two copies). In general, most of the time the cells are alive at this point. Further inter phase subdivided into gap-1 phase, synthesis phase, and phase-second gap.

Pro phase. At the pro phase stage, DNA began packaged or packaged into chromosomes. Chromosome is the densest structure of DNA packaging. Necessary DNA packaged into chromosomes. In early pro phase, the chromosomes began to appear under the microscope. Because at this stage, has been preceded by chromosomal DNA replication (two chromatids: 2c, two chromosomes: 2n), then the chromosome was composed of the twin chromatids are linked at the centromere. The centromere is a constriction region on the chromosome. In late pro phase, the chromosome appears to be solid and thicker and composed of a pair of chromatids. Each cremated is actually a package of DNA replication. In other words, paired chromatids are linked by a body of the centromere is a twin pack each copy (replica) DNA replication in the inter phase stage. The centromere is binding on both chromatids is considered as part of the DNA in the chromosomes that have not made the most recent replication and divide.

Meta phase. At the stage of metaphase chromosomes in pairs with each other. One pair of chromosomes consists of two chromosomes (2n). Each pair of chromatids of chromosomes made up of (2c) that put themselves on the field division. This field is a field placement division of chromosomes before dividing into polar the chromated cleavage. Thus, the chromosomes lie in the division with the goal of keeping the amount of DNA information to be given to the new daughter cells which really flat and the same amount.
Anaphase. At the stage of anaphase, chromatids begin to move towards the poles seem cleavage. Chromatid was unable to move itself, but must be withdrawn by the yarn from mikrotubul centrioles. Mikrotubul an interesting yarn called mikrotubul kinetochore chromosomes. Since the beginning of the core cleavage (early prophase), the yarn has been arranged in parallel mikrotubul linking centrioles to centrosome (the area near the nucleus of cells that normally contain centrioles) with the centromere through the kinetochore. Kinetochore is part of the chromosome (near the centromere) attachment for spindle threads. In animal cells, the field tends toward cleavage centrioles located at each pole of the cell. Each pole is the goal direction of movement of chromosomes (or chromatids, while it is in the attachment of the centromere). In plant cells there is no centrioles, but the division remains directed toward the pole of cleavage by a centrosome, but it does not contain threads sentriol. The way that mikrotubul chromosome kinetochore moves is by shortening mikrotubul. At the kinetochore, such mikrotubul dissociating (parsing) speed. Thus, the anaphase stage of producing a copy of the first but paired chromosomes (1c, 2n). Each copy of chromosome moves toward the pole division.

Telophase. In the early stages of telophase, the chromosomes (2n, and 1c) have been completed in polar division. Mikrotubul nonkinetokor (ie mikrotubul uninteresting chromosomes) extend the cell. Twin core has started core wrapped with envelope membranes. Chromatin threads started to loose. The final stage of telophase followed by cytokinesis.

Stage of cytokinesis. At the stage of cytokinesis occurs, followed by cytoplasmic division septum formation of new cells. Bulkhead separating the two nuclei into two daughter cells. In animal cells, cytokinesis begins during telophase stage ends. In late telophase occurred parsing spindle threads. Then immediately formed a narrow ring of microfilaments in the former region equatorial plane. This contraction in the direction in which cause deep cracks on the cell surface, followed by the contents of two cells permbagian separately. In plant cells have tough cell walls. Therefore, how cytokinesis of plant cells differ from animal cells. Plant cells that have been mengalam karokinesis bulkhead immediately formed around the former field of cell division. This bulkhead initially form from membrane vesicles derived from Golgi bodies. Vesicles are directed along mikrotubul in the equatorial plane. Vesicle-vesicle fusion was then experiencing the membrane form, and followed by the formation of new cell wall.

Treat your back

Good posture can prevent back pain problems, even digestion. Therefore, your daily program live for 12 minutes to straighten your back.

2 minutes. In the morning, stand in front of the mirror, the body is facing sideways. Make sure the ear, shoulder, hip, knee, and ankle form a straight line. Observe the feeling that arises when the body has really been straight.

1 min. Check your office chair. Make sure the foot planted on the top floor and eye position parallel to the computer screen or your laptop. When the position of tables and chairs more, use the support to the foot does not hang on the ground.

3 minutes. Check your posture six times a day. Each is 30 seconds. Do not forget during the sitting, the position of the shoulders down and gravitate toward the rear, while the thigh parallel to floor. In order not to forget, set an alarm reminded in a PDA or on your computer.

5 minutes. A short break and a walk around the office for 60 seconds. Therefore, standing can improve posture. Do it five times during working hours.

1 min. Before bed, take 60 seconds to find a comfortable sleeping position, sideways, or supine. To pose sideways, put a pillow between your knees.

The enchantment of Indonesian submarine

Feel the sensation when the body surf in the collection of small to giant-sized reefs that grow in sandy seabed, coral walls along tens of meters, followed by a lively movement of a variety of reef fish and marine life forms and colors with a gorgeous body. If you want to feel like Superman flying, you do not need to fantasize about having wings. Indonesian underwater world can realize your desire to fly the most beautiful places on this planet. Panorama that can easily be found in this maritime country. With a length of 95.181 kilometers of the coast or the second longest in the world, humble surge with a variety of reef fish on the surface and bottom water, cave, up the mountain under the sea. Waters of Bunaken Island, North Sulawesi is a small example of the nirvana that. Divers can be passed with exotic fish, such as Napoleon wrasse (Cheilinus undulatus), and a giant green turtle (Chelonia mydas). On the beach Hukurila in Ambon, Maluku, and Wasage Beach on the island of Buton, Southeast Sulawesi, fans adrenaline challenge will be presented with views of caves under the sea.

In the southwest, Mangehetang Island, Sangihe, North Sulawesi, the diver can see underwater mountain at a shallow enough waters to the point of the mountain crater eight meters deep. Banyknya almost countless dive sites that exist in the homeland of Indonesia. The potential is so vast and each point offering spectacular diving underwater unique and different. Diving tours in the homeland Indonesia started developing since the early 1980s. Special interest also led to the birth lovers of diving clubs, and tourist resort with dive operators service offering objects with tremendous experience. With the emergence of diving tourism objects, the interest of society to recognize this sport continues to grow. The growing interest of the community was at least as reflected in the exhibition Indonesia and Extreme Deep Indonesia 2010 in Jakarta on March 12-14 ago. With 20.000 rupiahs admission per person, from morning until night thousands of visitors from inside and outside the country crowded the booth stores tools sellers and agents, scuba diving tours.

If countries in mainland Europe is able to stimulate tourists to the exoticism of their artificial construction, not an overstatement that dive tour operators and tourist resort services raise sea superiority in these equatorial countries, namely Indonesia.

History of the sun age

As with all God's creatures that live on this earth has aged, as well as the other objects also have the age, including homes, cars, trains, earth, moon and so on. In short all god's creation and there was no time beginning the final time. Long between the beginning and the end is what is meant by age, or age. Sun also has a life of course. There was a time there during the birth and death. If the human age is only a few years, the sun has until billions of years old. When compared to the age of the earth by the time since there are humans on Earth until now then ever human being on this earth just a little course, if the age of the earth's age of man. Now we know that the sun was shining over to all incessantly from the first billions billion years ago until now. Light emitting means or the exertion of energy, meaning spent fuel. Look at the cars that run out of energy and must therefore spent fuel, gasoline or diesel fuel. So did the lights, ships or aircraft, time, human and other. What about solar? Same thing. The sun radiates as much light as 380,000,000,000,000,000,000,000 watts per second, a huge amount. We enjoy a small portion of the earth, which makes the possibility of living here. From where the sun get its fuel? He obtained by eating his own, meaning that the body itself became the sun for fuel. So why so long to bear, no end to have billions of years? Agency must have been in the sun someday. According to astrophysical science experts about 5 billion years from now.

There are many theories put forward by experts of the starting formation of the sun, but in general they expressed the same thing that the sun is the origin of the gas clouds, gathering in a large place in space. The collection of this gas cloud evolution occurs so that takes a very long time. A large part of gas clouds is very unusual. Clouds of this gas comes from power or energy in the form of light emitted from stars in the vicinity. This is in accordance with the laws of natural science. All the objects or the mass is a collection of power very much. Each object can be turned into energy, provided that human beings can liberate energy contained in them. This was evidenced by the explosion of a nuclear bomb or hydrogen bomb at Eniwetok in 1952, a small island in the territorial sea of the United States Pacific region. Similarly the sun gives energy to all directions, just like the process of nuclear bombs. Although the sun takes as many as 657 million tons every least, the sun was still able to survive another five billion years or perhaps longer. This has been taken into account Martin Schwarzchild astronomers from Princeton University and the Allan Sandage of Palomar United States. Approximately 5 billion years from now the sun will begin to inflate, the photosfer colder, but overall solar energy produced will be greater. Approximately one billion years later, the temperature of the earth on average reached 500 degrees Celsius. Some super beings could still live on earth with a fairly good protective gear. At that time the sea was boiling and sugar so that the steam discharged into the ocean to melt like sugar because it was only a mere salt.

Then after life on earth has been destroyed completely, the sun will be a shrinkage shrinking back. In such circumstances it becomes unstable. Decreases faster and faster. A few million years the sun will cool, he stayed like a giant black ball that lost all its light. There are only among us who may ask many questions, from which astronomers know the life history of the sun to a thousand million years to come. The answer is they can watch the stars scattered around us. Because the sun also a star, then the sun as well as them. Now there are stars who will be born, being born, the old, will die and many others.

Jenis-jenis polimer dan manfaatnya

Karet alam atau karet mentah memiliki sifat fleksibel, harganya relative ringan tapi daya sambung dan daya rekat jauh lebih rendah disbanding karet sintesis bila dibuat perekat. Karet alam tidak bisa dipakai untuk penyambung plastic. Perekat yang dipakai dan terbuat dari karet sintesis atau karet alam tidak tahan terhadap bahan pelarut minyak bahan oksidasi dan sinar ultraviolet, mudah sekali rusak bila terkena panas. Tahan terhadap panas pada suhu 35-40 derajat Celsius sebelum divulkanisasi, jika divulkanisasi tahan terhadap panas 70 derajat Celsius. Karet alam larut dengan baik pada pelarut hidrokarbon. Perekat ini berguna untuk benda ringan seperti kain karet busa yang mengelupas pada bebang 3 kilogram/cm2 pada suhu kamar.

Bila karet alam ini divulkanisir ia akan menjadi tahan panas dan kekuatan mengelupas sampai dengan 6 kilogram/cm2. Salah satu dari keunggulan dari solusi karet alam tidak beracun, pelarut yang dipakai tidak menyengat dan tidak mudah terbakar, viskositas dari solusi ini kira-kira 25 persen. Karet Stiren butadin adalah karet sintetik termasuk yang luas permukaannya dan pemakaiannya dan murah harganya dibangingkan dari karet alam. Karet Stiren Butadin termasuk perekat interior. Dari perekat ini berguna untuk karpet, karet busa dan konstruksi mobil untuk menyambung karet kelogan karet ini tidak berguna untuk PVC. Pelarut yang digunakan biasanya nafta.

Karet nitril karboksil adalah karet yang mengandung gugus asam karboksilat. Perekat yang dibuat dari bahan ini tidak saja memiliki daya rekat yang tinggi terhadap logam tapi juga mempercepat reaksi resinya terhadap senyawa lain yang gunanya member kekuatan adhesive dan kohesif, dan lebih tahan minyak. Karet alam adalah polimer hidrokarbon tak jenuh. Senyawa ini secara komersial diperoleh dari getah karet. Struktur kimianya sebagian dijelaskan pada abad ke 19 jika dipanaskan tanpa udara (isoprene).

Kebanyakan karet memiliki ikatan molekul lebih dari 10000000. Besarnya variasi menurut metode pengolahan. Karet mentah mengandung kira-kira -1, -2, -3 persen air dan sedikit bahan organic, serta poliisoprena. Penggolongan suatu jenis konvensional dilakukan dasar-dasar visualisasi atau sifat-sifat yang dapat dilihat oleh mata, misalnya warna karet, adanya endapan serta noda-noda lainnya. Sistem penggolongan tersebut sama sekali tidak memberikan informasi tentang sifat-sifat karet teknis dari karet mentahnya (terutama untuk barang-barang jadi karet mentahnya) dan tidak ada hubungan langsung antara warna gelombung udara dan noda-noda tertentu lainnya dengan sifat-sifat teknis karet yang menjadi persyaratan barang-barang jadi karet yang diproduksi. Polimer alami juga sangat penting untuk kehidupan organisme. Tanpa struktur polimer alam seperti sellulosa pada tanaman atau protein bahwa konstruksi urat dan otot hewan. Hewan tidak hidup serta tanaman tidak dapat berdiri diatasnya tali gravitasi. Kita semua diciptakan laut, dimana membrane halus kita didukung oleh aliran di dalam air. Enzim tanaman dan hewan bahwa katalis semua reaksi biokimia penting sebagai polimer asam amino. Terakhirnya, dioksiribosanukleat (DNA) merupakan bahan genetic. Warisan semua tanaman dan hewan-hwan adalah polimer asam nukleat.

Bentuk polimer datang dari yunani (poly) dan menunjukkan sebuah molekul besar yang dibuat dari banyak bagian makromolekul adalah suatu bentuk sinonim dari polimer. Polimer-polimer dibuat oleh garis bersama molekul sederhana yang disebut dengan monomer (bagian tunggal).

The Age of Earth

Geologists have calculated how much the age of the earth. This can be estimated from the level of damage from a few specific elements that existed at the Earth's crust. Atoms of uranium and thorium the longer the less, changing gradually into a variety of elements including radium which ended up being a black tin atoms. Rate this change has been investigated in the laboratory, how long of an element into another element. Elements downsizing it happens regularly.

The stones of the mountain or archaeological objects can be used as a tool to calculate the ratio of mineral elements such as lead, uranium, radium, so that can know a lot of comparisons and the reduction of the investigated objects, then they will know how long the reduction process, and thus also be shown how the stone age. Similarly age of the earth can be known in a similar way. They estimate the age of the earth between 3000 to 5000 million years ago. The calculation can be done any other way to calculate how much salt is contained in the oceans today.

The experts firmly believe that when at first there was the ocean, the water is not salty. What causes sea water taste salty is because the rivers that come from the mainland brought a variety of substances that make the sea water became salty taste. After carefully calculated how much salt water content is increased every year, so know how old the earth. Among all the planets in this solar system, only allowing the existence of life. Nevertheless, still uncertain whether other planets have life, though different from what exists on earth.

Doubts were depicted on American spacecraft, Voyager II, which was launched on 20 August 1977 to Jupiter, Saturn, Uranus and perhaps then he would shy away from the solar system to the next adventure for for about 1000 million years between the stars in the Milky Way. On the plane, played the messages from the President of the United States and prosperous congratulations sayings from various nations of different languages who knows maybe there is a civilized life. Reaction of civilization would be provoked in this way. The leading scholars, both her undergraduate astronomy, geology or biology. All agreed that life on this earth that life runs in evolution or a gradual slow. It means that now is not the same man to man hundreds of thousands of years ago. It is also not the same shape of the animal's body is now with the animals millions of years ago. Origin of life is from one cell, which then evolve rapidly.

These cells then transformed into plants or animals like this now. Change is a very long time consuming. Forms of life on earth in accordance with the terms and conditions that owned the earth. Similarly, life on earth will end when the terms and conditions do not permit the earth again. For example if it was time the sun was enlarged, so the bigger of the sun so very close to the earth, of life on earth ended. What is the most difficult questions to be answered is the biggest question of all time is where the sudden advent of life or soul of a cell. If the theory of evolution's way of thinking can make a sense, but the arrival of life or soul for animals, plants and humans are not answered by these scholars.

Redox Reactions

(Picture downloaded from http://kimia.upi.edu/utama/bahanajar/kuliah_web/2008/SUVENTI%20IKA%20PUSTIAWATI%200602664_/images/gambar1.jpg)

All the reactions mentioned in the sections on the front is the ion incorporation reaction, whereby the oxidation number of species-species that reacts is not changed. But there are a number of reactions in which oxidation state changes are accompanied by electron exchange between the reactants.

The process is electrochemical Redox reaction (reduction-oxidation), in which this reaction the energy released by the spontaneous reaction turned into electricity or where electricity is used so that the reaction could non-spontaneously occur. Which one is the reduction oxidation reduction and oxidation is the opposite of the increase in oxidation number.

The term oxidation proved or applied to the process of taking oxygen from a substance or substances. Reduction of itself regarded as a process where oxygen is taken from a substance, then the arrest is also called the reduction of hydrogen so that hydrogen loss should also be referred to as oxidation.

Download full article in Bahasa Indonesia here