Effect of Dielectric on Capacitance

IMPORTANT

Effect of Dielectric on Capacitance: Overview

This topic covers concepts, such as, Effect of Dielectric on the Value of Capacitance, Induced Charges on the Dielectric Slab Kept inside a Parallel Plate Capacitor & Induced Charges on the Conducting Slab Kept inside a Parallel Plate Capacitor etc.

Important Questions on Effect of Dielectric on Capacitance

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The two plates of a parallel plate capacitor are 4 mm apart. A slab of dielectric constant 3 and thickness 3 mm is introduced between the plates with its faces parallel to them. The distance between the plates is so adjusted that the capacitance of the capacitor becomes 23rd of its original value. What is the new distance between the plates?

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Two conducting square plates with length l are arranged parallel to each other at a distance d(1). The space between the plates is filled with a dielectric of relative permittivity εr=4 up to a length x=l/3. The upper plate is given a charge Q and the lower plate is given a charge -Q as shown in the figure. If Q=6 μC then find how much charge (in μC) is present on the portion of upper plate which is in contact with the dielectric?

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Capacity of a parallel capacitor with dielectric constant 5 is 40 μF. Capacity of the same capacitor in μF when dielectric material is removed is

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A parallel plate capacitor with plate area 1 m2 and plate separation 1 mm is charged at the rate of 25 V s-1. The dielectric between the plates has a dielectric constant k. If the displacement current through the capacitor is 2.21 μ A then the value of k' is nearly

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A parallel plate capacitor has a capacity 80×10-6 F when air is present between its plates. The space between the plates is filled with a dielectric slab of dielectric constant 20. The capacitor is now connected to a battery of 30 V by wires. The dielectric slab is then removed. Then the charge passing through the wire is

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In a parallel plate with air capacitor of capacitance 8 μF, if the lower half of the air space is filled with a material of dielectric constant 3, its capacitance changes to:

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The radii of two spherical conductors A and B are in the ratio 3:5 Conductor 'A' is in air while B is surrounded by a meditm of relative permittivity 6. The ratio of the capacitances of A and B is

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A parallel plate air condenser has a capacity of 20 μF. What will be the new capacity in μF if a marble slab of dielectric constant 8 is introduced between the two plates ?

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What is the effect of dielectric on capacity of a parallel plate capacitor.

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Derive an expression for capacity of a parallel plate capacitor filled with dielectric.

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On immersing a parallel plate capacitor in oil what will be the effect on its capacitance? The dielectric constant of oil is 2.

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The plate separation of a parallel plate capacitor is d. If a metallic plate of thickness d/2 is placed in the space between plates not touching any plate, then what will be effect on its capacitance?

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On filling the space between the plates of a parallel plate capacitor with some dielectric, its capacitance increases five times. What is the dielectric constant of this material?

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The potential energy stored in the region between plates of a capacitor is U0. If a dielectric slab of r now fills the space between the plates completely then new potential energy will be

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For capacitor shown in the figure, find capacitance between A and B. Area of each plate is A and the plate separation is d.

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For the capacitor shown in figure, find the capacitance. Area of each plate is A, and the plate separation is d.

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On filling the space between a 2 μF air capacitor by mica its capacitance becomes 5 μF. Calculate the dielectric constant of mica.

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A parallel plate capacitor with air as medium is charged to a potential difference V using a voltage supply. After it is disconnected from the voltage supply, the space between plates is completely filled by a dielectric. Explain with reasons the changes observed in the energy.

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A parallel plate capacitor with air as medium is charged to a potential difference V using a voltage supply. After it is disconnected from the voltage supply the space between plates is completely filled by a dielectric. Explain with reasons the changes observed in the electric field.

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A parallel plate capacitor with air as medium is charged to a potential difference V using a voltage supply. After it is disconnected from the voltage supply the space between plates is completely filled by a dielectric. Explain with reasons the changes observed in the capacitance.