(a) Two charged bodies, A and B are suspended from a fixed point with the help of silk threads as shown in the figure. If A is positively charged can we identify the nature of charge on 'B' ?

(b) A negatively charged conducting sphere A and a neutral sphere B are kepton insulating stands and brought cose to each other. The charge distri-bution is as shown in the figure.
Is B charged ? What type of force exists between A and B ?

Explanation

(a) From the figure, we know that there is a repulsive force between A and B. A repulsive force exists between like charges. Since A is positively charged, B must be positively charged. (b) If we observe the figure, we see that on B,positive charge is distributed on left side whereas, negative charge is distributed on the right side. As they are equal in magnitudes, the net charge on B is zero. Redistribution of charges has taken place in B when it is placed near a negatively charged body A because of electric induction. There will be attractive force between A and B.