Target Exam

CUET

Subject

Physics

Chapter

Electrostatic Potential and Capacitance

Question:
If the capacitor is charged in presence of dielectric and then the dielectric is removed afterwards, what will be the change in potential ?
Options:
potential increases
potential decreases
remains constant
can't say
Correct Answer:
potential increases
Explanation:

$C = \frac{\epsilon_0 K A}{d}$

$V = \frac{Q}{C}$

$C_{\text{with dielectric}} = K C_0$

$V_{\text{initial}} = \frac{Q}{K C_0}$

$C_{\text{after removal}} = C_0$

$V_{\text{final}} = \frac{Q}{C_0}$

$V_{\text{final}} = K \cdot V_{\text{initial}}$

The potential increases.