Electrostatics

Two like charges

• attract each other

• repel each other

• neutralize each other

• must be neutrons

Coulomb's law says that the force between any two charges depends

• directly on the size of the charges

• inversely on the square of the distance between the charges

• directly on the square of the distance between the charges

• inversely on the size of the charges

When the distance between two charges is halved, the electrical force between the charges

• quadruples

• doubles

• halves

• reduces to one fourth

The SI unit of charge is the

• Newton

• Ohm

• Coulomb

• Joule

Conservation of charge means that

• the total amount of charge in the universe is constant

• charge can neither be created nor destroyed

• electrons themselves can be neither created nor destroyed

• no experimenter has ever seen charged destroyed by itself

Particle A has twice as much charge as particle B. Compared to the force on particle A, the force on particle B is

• four times as much

• two times as much

• the same

• half as much

If you comb your hair and the comb becomes positively charged, your hair becomes

• positively charged

• negatively charged

• uncharged

A difference between electrical forces and gravitational forces is that electrical forces include

• separation distance

• repulsive interactions

• the inverse square law

• infinite range

In a good insulator, electrons are usually

• free to move around

• free to move around after an impurity has been added

• tightly bound in place

• not moving at all

Objects can be charged by

• friction

• conduction / contact

• induction

• all of these