Question

A dielectric slab of thickness $d$ is inserted in a parallel plate capacitor whose negative plate is at $x=0$ and the positive plate is at $x=3d$. The slab is equidistant from the plates. The capacitor is given some charge. As $x$ goes from $O$ to $3d$,

• A. The magnitude of electric field remains the same
• B. The direction of the electric field remains the same
• C. The electric potential increases continuously
• D. The electric potential increases at first, then decreases and again increases

Answer 1

Answer: (B), (C)

The direction of the electric field remains the same
The electric potential increases continuously

The direction of electric field will remain same throughout ( $\overrightarrow{E}$ [ direction is from -ve plate to +ve plate ] ) (B)

$\Rightarrow v=\overrightarrow{E}.d$

As potential increases as we move in the direction of $\overrightarrow{E},$ So, potential will increase as we from $x=0$ to $x=3d.$

Hence, both the options are correct.