Getting Charged Up
Friction
Charging by friction requires rubbing.
Conduction
Charging by touching is called conduction.
Induction
Charging without touching induction.
Lightening
Lightning starts with negative charges moving down to the ground, and positive charges move up from the ground. Lighting can be seen to travel from the ground to the cloud, as the positively charged upward leader moves up to meet the negatively charged stepped leader coming from the clouds, creating an explosion of light.
Experiment: Separating Pepper from Salt
The comb begins with a neutral charge. It has an equal number of protons and electrons. When we rub the comb through our hair, electrons are transferred to the comb, giving it a net negative charge and creating static electricity. The pepper is attracted to the comb more than the salt for two reasons. The pepper is lighter and easier to be moved by the static electric forces than the heavier salt. The neutrally charged pepper is attracted to it. The pepper is also more easily polarized than the salt. Its positive and negative charges are more easily pulled apart to either end of its particles. The positive end of the pepper particle is pulled up to the negatively charged comb. The electrons of the chloride in the salt are more tightly bonded to the positively charged sodium in the salt particle. Sodium is a metal and a conductor of electricity. It strongly attracts electrons to itself; and so it is not as easily polarized.
