Question

When a comb rubbed with dry hair attracts pieces of paper. This is because the
A. Comb polarizes the piece of paper
B. Comb induces a net dipole moment opposite to the direction of field
C. Electric field due to the comb is uniform
D. Comb induces a net dipole moment perpendicular to the direction of field
E. Paper acquires a net charge

Answer 1

This aspect talks basically on static electricity [electrostatic] whereby a zero charged material can be induced due to friction and charges set up. The need for us to know that there are charges carrying material that can easily contact another material with a neutral or zero charge

Complete step by step answer: irstly, when the comb is used to rub dry hair, it always acquires a negative charge or electron which the hair carries, where the comb is induced with the electron gotten from the hair then immediately the comb which is negatively charged comes in contact with the piece of paper which is gets polarized by the comb, there is therefore bound to be attraction between them. This therefore explains unlike charges attracting each other.
Because there is an opposite charge to that of the paper the correct option is Option A. The law of electrostatics holds that unlike charges attract and like charges repel.
The answer is Option A, comb polarizes the piece of paper.

Note: Other applications involve rubbing the said comb on a piece of a person’s shirt or sleeve and still apply on a piece of paper. Another application or example is found in glass rods rubbed with silk and also ebonite rubbed with fur. The charges which are unlike are positive and negative (electrons and protons) whereas charges which are alike are positive-positive, negative-negative (north pole repel north pole).