Parts of an atom
All matter is made up of small indivisible particles called atoms. Each atom conisists of three type of subatomic particles.
Click on the video to learn more about these subatomic particles...
Video 1
Mass and charge
Click on the chart to learn more...
Since atoms are very small, we use the term relative, comparing the particle/ atom to 1/12 the mass of carbon 12.
But.... why carbon 12? Click the chart to learn more.
Nucleon
Particles in the nucleus (proton/ neutron) are called nucleons.
Finding the charge of an electron
In 1909, Robert Millikan conducted an oil drop experiment to determine the charge of one electron. By spraying a fine negatively charged droplets of oil between two metal electrodes, he then altered the electric field strength to produce an upward electrical force to balance the downward gravitational forces (from the weight of the oil drops). Time for you to recreate the famous Millikan Experiment using the two simulations below.
Click the images below to begin.
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Note: m= mass of oil droplet, g= gravitational acceleration, E= electrical field strength and q= charge of the electron
As the charge of the electron is very small, to make life simpler, we used the term relative charge instead (relative meaning compare to charge of one proton). Therefore showing that the relative charge of the electron as 1- and relative charge of the proton as 1+.