Question

a What are the qualitative similarities and differences between Coulomb's Law and Newton's Law of Universal Gravitation. (be brief and specific)

b. Describe what happens to an uncharged conductor when a positive charge is brought near. Explain any forces thatare exerted on the conductor. A sketch or drawing may be helpful.

c. Describe what happens to an uncharged insulator when a positive charge is brought near. Explain any (net) forces that are exerted on the insulator. A sketch or drawing may be helpful.

Answer 1

a.

similarities between Coulomb’s law and Newton’s law universal gravitation:

1. Both obeys inverse square law
2. Both laws describe central forces

Differences between Coulomb’s law and Newton’s law universal gravitation:

1. Coulomb’s law describes attractive or repulsive force while Newton’s law universal gravitation only attractive force.
2. Coulomb’s law explains the dependence of surrounding medium on electric force while Newton’s law universal gravitation shows that the gravitational force is independent of surrounding medium

b.

when a positive charge is brought near an uncharged conductor, certain quantity of negative charge is induced on the near side and equal quantity of positive charge is induced on the far side of the conductor due to electrostatic induction.

The positive charge exerts an attractive force on the side of the sphere having -ve charge and positive charge exerts an repulsive force on the side of the sphere having +ve charge.

c.

no effect can be seen when a positive charge is brought near an uncharged insulator. electrostatic induction can not takes place in the case of an insulator and it doesn’t acquire charge due to induction.

Since, no charge is induced on the insulator it does not experience any electric force due to the positive charge.