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The potential difference between the plates of a parallel plate capacitor is 10 V and separation is 5 cm. Find the energy density between plates. ε0=10-11 F m-1

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Important Questions on Electrostatic Potential and Capacitance

HARD
5 μF capacitor is charged fully by a 220 V supply. It is then disconnected from the supply and is connected in series to another uncharged 2.5 μF capacitor. If the energy change during the charge redistribution is X100 J then value of X to the nearest integer is :
MEDIUM
A 60 pF capacitor is fully charged by a 20 V supply. It is then disconnected from the supply and is connected to another uncharged 60 pF capacitor in parallel. The electrostatic energy that is lost in this process by the time the charge is redistributed between them is (in nJ ) ________
MEDIUM
10 μF capacitor is fully charged to a potential difference of 50 V After removing the source voltage it is connected to an uncharged capacitor in parallel. Now the potential difference across them becomes 20 V. The capacitance of the second capacitor is :
MEDIUM

In the circuit given below, the capacitor C is charged by closing the switch S1 and opening the switch S2. After charging, the switch S1 is opened and S2 is closed, then the maximum current in the circuit

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If the capacitance of a nanocapacitor is measured in terms of a unit u,  made by combining the electronic charge e, Bohr radius a0, Planck's constant h and speed of light c then
HARD
Two capacitors with capacitance values C1=2000±10 pF and C2=3000±15 pF are connected in series. The voltage applied across this combination is V=5.00±0.02 V. The percentage error in the calculation of the energy stored in this combination of capacitors is __________.
MEDIUM
A capacitor C is fully charged with voltage V0. After disconnecting the voltage source, it is connected in parallel with another uncharged capacitor of capacitance C2. The energy loss in the process after the charge is distributed between the two capacitors is :
EASY
A 10 mF capacitor has been charged to a potential of 100 V. Suddenly if it explodes, the energy given out is
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A parallel plate air capacitor has capacity C farad, potential V volt and energy E joule. When the gap between the plates is completely filled with dielectric
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The energy stored in the electric field produced by a metal sphere is 4.5 J. If the sphere contains 4 μC charge, its radius will be: Take:14π0=9×109 N m2 C-2
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The potential differences that must be applied across the parallel and series combination of 3 identical capacitors is such that the energy stored in them becomes the same. The ratio of potential difference in parallel to series combination is

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The energy per unit volume for a capacitor having area A and separation d kept at potential difference V is given by
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A capacitor of capacitance C is connected in series with a resistance R and DC source of emf E through a key. The capacitor starts charging when the key is closed. By the time the capacitor has been fully charged, what amount of energy is dissipated in the resistance R?

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MEDIUM
A parallel plate capacitor has plate of length l, width w and separation of plates is d. It is connected to a battery of emf V. A dielectric slab of the same thickness d and of dielectric constant K=4 is being inserted between the plates of the capacitor. At what length of the slab inside plates, will the energy stored in the capacitor be two times the initial energy stored?
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A 10 μF capacitor is charged to 500 V and then its plates are joined together through a resistance of 10 Ω. The heat produced in the resistance is
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A circuit has a self-inductance of 1 H and carries a current of 2 A. To prevent spark, when the circuit is broken, a capacitor which can withstand 400 V is used. The least capacitance of the capacitor is,
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A parallel plate capacitor whose capacitance C is 14 pF is charged by a battery to a potential difference V=12 V between its plates. The charging battery is now disconnected and a porcelain plate with k=7 is inserted between the plates, then the plate would oscillate back and forth between the plates with a constant mechanical energy of _______ pJ.

(Assume no friction)

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A capacitor with capacitance 5 μF is charged to 5 μC . If the plates are pulled apart to reduce the capacitance to 2 μF, how much work is done?
HARD
A parallel plate capacitor having capacitance 12pF is charged by a battery to a potential difference of 10V between its plates. The charging battery is now disconnected and a porcelain slab of dielectric constant 6.5 is slipped between the plates. The work done by the capacitor on the slab is
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A parallel plate capacitor has a uniform electric field E in the space between the plates. If the distance between the plates is d and the area of each plate is A, the energy stored in the capacitor is: ε0= permittivity of free space)