Two isolated metal spheres are identical. They are electrically neutral and are touching. An electrically charged rod is then brought near the spheres without touching them, as the drawing shows. After a while, with the rod held in place, the spheres are separated, and teh rod is then removed. The following statements refere to the mases `m_(A)` and `m_(B)` of the spheres after they are separated and the rod is removed. Which of the follownig statements is true?

Options

A. `m_(A)=m_(B)`
B. `m_(A)gtm_(B)` if the rod is positive
C. `m_(A)gtm_(B)` if the rod is negative
D. `m_(A)gtm_(B)` irrespective of the charge (+ve or -ve) on the rod

Answer

D

Explanation

If the rod has +ve charge, by induction a negative charge appears on A and a positive charge o B. When A has negative charge it has more mass (surplus electrons) than B.