Question

The electric force between two charged particles becomes weaker with increasing distance. Suppose instead that the electric force was independent of distance. In this case, would a charged comb still cause a neutral insulator to become polarized as in Fig. 21.8? Why or why not? Would the neutral insulator still be attracted to the comb? Again, why or why not?

Short answer

There is no force of attraction between the comb and the neutral insulator.

Step-by-step solution

Explanation of whether a charged comb will cause a neutral insulator to become polarized.

For two bodies to be attracted, opposing charges must be piled up or generated on both of them. Because the neutral insulator is charge-free, it cannot induce charges by itself or by any other way without physical contact to allow charge transfer. Thus, there is no attraction between the comb and the insulator and no polarization.

Explanation of whether the neutral insulator will be attracted to the comb.

No, the neutral insulator will not be attracted because there is no charge induced on its surface. Thus, there is no net force because polarization will be possible only if work is done on the charges by a force on the charges of the comb.