The force between two magnetic poles varies ______ as the square of the distance betwee them.

The force between two magnetic pole can be

Force between two charges varies directly as the square of the distance between them. !

The force between a magnetic pole and a magnetic substance is

Fill in the blank spaces with appropriate answer: The force between two magnetic poles is _________ and _________.

Fill in the blank spaces with appropriate answers: Coulomb force between two point charges ________ on the nature of the dielectric medium separating them.

Find the Coulomb force between two protons in a nucleus, if the average distance between two protons in a nucleus is 6 fm.

State whether the force between two charges will be changed when a third charge is brought near them.