1. Principles of electrostatics
1.1. charging by rubbing
1.2. charging by induction
1.2.1. induction is the production of electric charge on the surface of a conductor under the influence of an electric field
1.2.2. earthing process
1.3. crazy action of paper
1.3.1. attractive force>repulsion force
2. Electric Field
2.1. electric field lines
2.1.1. the lines must begin from positive charges and end on the negative charges
2.1.2. the number of lines drawn leaving a positive charge or ending on a negative charge is proportional to the magnitude of the charge.
2.1.3. no two field lines can cross each other
2.1.4. the electric field between parallel oppositely charged plates is uniform at the central region
2.1.5. the electric lines of force are closer to each other in a stronger electric field
3. Laws of electrostatics
3.1. electrically charged
3.1.1. negatively charged
3.1.1.1. amber(rubbed by fur)
3.1.1.2. rubber(rubbed by fur)
3.1.1.3. polythene(rubbed by wool)
3.1.2. positively charged
3.1.2.1. glass(rubbed by silk)
3.1.2.2. perspex(rubbed by wool)