Question

A large non-conducting sheet M is given a uniform charge density. Two uncharged small metal rods A and B are placed near the sheet as shown in the figure (30-Q4).
(a) M attracts A.
(b) M attracts B.
(c) A attracts B.
(d) B attracts A.
Figure

Answer 1

Answer:

Explanation:

a) M attracts A.

(b) M attracts B.

(c) A attracts B.

(d) B attracts A.

Since the non-conducting sheet M is given a uniform charge, it induces a charge in the metal rod A, which further induces a charge in the metal rod B, as shown in the figure. Hence, all the options are correct.

Answer 2

All the options are correct.

Explanation:

• The non-conducting sheet M is provided with a uniform charge, which in the metal rod A, persuades a charge. In metal rod B, this further leads to the induction of charge as indicated in the figure above.  
• The rod A’s face faces M. This will increase a charge that is induced on the surface, which is opposite and equal to the charge on M. therefore, A is attracted.
• Now, from the far distance of A, the charge that is opposite and equal to the A’s nearer end will be induced. As before, the charge opposite to M is induced nearer to the B’s end. Hence, this is also attracted by M.
• B and A have opposite charge polarities on the sides. Therefore, they attract each other. Hence, all the given options are answers.