Hukum Ohm

Ahli fisika berkebangsaan jerman yang bernama George Simon Ohm, telah berhasil menemukan hubungan antara besar beda potensial dengan nama hukum ohm berbunyi sebagai berikut. Kuat arus yang mengalir dalam suatu penghantar sebanding dengan beda potensial antar ujung - ujung penghantar itu jika suhu penghantar tetap.

Dari penghantar Ohm tersebut dapat dirumuskan bahwa:

V=I.R

Keterangan:

V = Beda potensial (volt)

I = Kuat arus (ampere)

R = Hambatan (Ohm)

Definition of Atom, Neutron, Proton and Electron

 Definition of Atom, Neutron, Proton and Electron

Atom is a very small unit in each month are around us. Atom consists of the three types of sub-atomic particles:

•  Electrons, which have a negative charge
•  Proton, which has a positive charge
•  Peutrons, which are not charged

Each element is uniquely distinguished by the number of protons contained in the atom of the element. Each atom has a number of electrons equal to the number of protons, if there are differences in these atoms are called ions.

Many other man-made elements, but they are usually unstable and spontaneously turned into a stable chemical elements through the process of natural radioactivity.
Although there are only 91 elements in nature, but the atoms can bond with each other happens to molecules and other types of chemical compounds. Molecules are made ​​up of many atoms. Molehkul water is a combination of 2 hydrogen atoms and 1 oxygen atom.

1. Neutron is a subatomic particle is not charged (neutral) and has a mass of 1.6749 x 10-27 (27 min) and mass 1.6726231 x 10-27 (min 27) pounds.
2. Protons are subatomic particles big positive with contect, and mass around 18,000 times the mass of an electron.
3. Electron is a subatomic particle that has a negative electric charge of 1.6 x 10-19 (19 min) and mass coulumb 9:10 x 10-31 (min 31) pounds.