Question

A rod $PQ$ is connected to the capacitor plates. The rod is placed in a magnetic field $\left(B\right)$ directed downward perpendicular to the plane of the paper. If the rod is pulled out of magnetic field with velocity $\overrightarrow{v}$ a shown in figure.

• A. Plate $M$ will be positively charged
• B. Plate $N$ will be positively charged
• C. Both plates will be similarly charged
• D. No charge will be collected on plaes

Answer 1

The correct option is A Plate $M$ will be positively charged

Force on positive charge in the rod is given by $q\overrightarrow{v}\times \overrightarrow{B}$ . Therefore positive charge will experience a force towards P and negative charge will experience a force towards Q.
Therefore P is positive wrt to Q. Therefore plate M will get positively charged and plate N will get negatively charged.