A parallel plate air capacitor of capacitance $$C$$ is connected to a cell of emf $$V$$ and then disconnected from it. A dielectric slab of dielectric constant $$K,$$ which can just fill the air gap of the capacitor is now inserted in it. Which of the following is incorrect?

 1 the potential difference between the plates decreases $$K$$ times. 2 the energy stored in the capacitor decreases $$K$$ times. 3 the change in energy stored is $$\frac{1}{2}CV^{2}\left ( \frac{1}{K} -1\right )$$ 4 the charge on the capacitor is not conserved.

Subtopic: Â Energy stored in Capacitor |
Â 71%
From NCERT
NEET - 2015
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A parallel plate condenser has a uniform electric field $$E$$ (V/m) in the space between the plates. If the distance between the plates is $$d$$ (m) and the area of each plate is $$A$$ (m2), the energy (joule) stored in the condenser is:
1. $$\frac{1}{2}\varepsilon_0{E}^2$$
2. $$\frac{{E}^2 {Ad}}{\varepsilon_0}$$
3. $$\frac{1}{2}\varepsilon_0 E^2 Ad$$
4. $$\varepsilon_0 EAd$$

Subtopic: Â Energy stored in Capacitor |
Â 90%
From NCERT
NEET - 2021
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A series combination of n1 capacitors, each of value C1, is charged by a source of potential difference 4V. When another parallel combination of n2 capacitors, each of value C2, is charged by a source of potential difference V, it has the same (total) energy stored in it, as the first combination has. The value of C2, in terms of C1, is then:

1. $\frac{2{C}_{1}}{{n}_{1}{n}_{2}}$

2. $16\frac{{n}_{2}}{{n}_{1}}{C}_{1}$

3. $2\frac{{n}_{2}}{{n}_{1}}{C}_{1}$

4. $\frac{16{C}_{1}}{{n}_{1}{n}_{2}}$

Subtopic: Â Energy stored in Capacitor |
Â 72%
From NCERT
AIPMT - 2010
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Two condensers, one of capacity $$C$$ and the other of capacity $$\frac{C}2$$ are connected to a $$V$$ volt battery, as shown in the figure.

The energy stored in the capacitors when both condensers are fully charged will be:
1. $$2CV^2$$
2. $${1 \over4}CV^2$$
3. $${3 \over4}CV^2$$
4. $${1 \over2}CV^2$$

Subtopic: Â Energy stored in Capacitor |
Â 83%
From NCERT
AIPMT - 2007
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