Q36 / 50 · Manipal (MET) 2023 · Physics
A charged capacitor when filled with a dielectric $K=3$ has charge $Q_0$, voltage $V_0$ and field $E_0$. If the dielectric is replaced with another one having $K=9$, the new values of charge voltage and field will be respectively
- A$3 Q_0, 3 V_0, 3 E_0$
- B$Q_0, 3 V_0, 3 E_0$
- C$Q_0, \frac{V_0}{3}, 3 E_0$
- Correct answerD$Q_0, \frac{V_0}{3}, \frac{E_0}{3}$
Solution
When charging battery is disconnected then charge remains constant, $V$ becomes $1 / K$ times and $E$ becomes $1 / K$ times.
So, new value of charge is $Q_0$.
New value of $V=\frac{V_0 \times 3}{9}=\frac{V_0}{3}$
New value of $E=\frac{E_0 \times 3}{9}=\frac{E_0}{3}$
Hence, the correct answer is option: 'D'.