OnlineCBT
Physics · Electrostatic Potential
हिन्दीGiven below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): When a dielectric medium is completely placed between the plates of a charged capacitor, the capacitance always increases by a factor \( K > 1 \). Reason (R): Polarization of the dielectric produces bound charges of opposite sign near the plates, which decreases the net electric field inside the dielectric for a given free charge on the plates. In the light of the above statements, choose the correct answer from the options given below:
Correct answer · Option 1
Both (A) and (R) are true and (R) is the correct explanation of (A).
Explanation
Due to polarization, \( E = \frac{\sigma - \sigma_p}{\varepsilon_0} = \frac{E_0}{K} \), reducing potential difference \( V = Ed \) for a given \( Q \), so \( C = Q/V = K C_0 \). Thus, (R) correctly explains (A).
