1. Charged by
1.1. Rubbing
1.1.1. If a surface is rubbed by an object, energy is passed on to the electrons that move from the surface to the object.
1.2. Induction
1.2.1. Charging a conductor positively
1.2.1.1. Bring a negatively charged rod near the conductor, then earth the conductor.After the finger is removed, then the charged rod, conductor becomes positively charged.
1.2.2. Charging a conductor negatively
1.2.2.1. Bing a positively charged rod near to a conductor, then earth the conductor. After the finger is removed, then the charged rod is removed, the conductor will be negatively charged.
2. Electric Field
2.1. Definition
2.1.1. Any region in which an electric charge experiences electric forces.
2.2. Charges of Electric fields
2.2.1. A positive point charge has electric field lines pointing outwards.
2.2.2. A negative point charge has electric field lines pointing inwards.
2.2.3. Note that the lines do not intersect each other and begin on positive charges and terminate on negative charges
2.2.4. If the unlike charges are further away, they are weaker. If they are nearer, they are stronger.
3. Basics of Static Electricity
3.1. Like charges repel.
3.2. Unlike charges attract.
4. Hazards of electrostactics
4.1. Sparks are easily produced by accumulated electric charges on an object. Possible ranging from electric shocks to explosions.
4.2. Lightning carries a huge amount of electric charge. Hazards ranging from starting a fire to death.
5. Applications of electrostatics
5.1. Photocopier
5.1.1. The drum of the photocopier is positively charged. When exposed to image, the toner sticks to the positive part of the drum, leading to the paper to be negatively charged.After transferring the toner to the paper by electric force, it is fused by the paper through heat.
5.2. Electrostatic Precipitaion
5.2.1. To remove dust particles from the chimney to reduce air pollution. They then become charged and stick to the walls of the chimney.