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प्रश्न
Define the capacitance of a capacitor and its SI unit.
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उत्तर
Capacitance
Capacitor is a device which is used to store charge. The capacity of a capacitor to store charge is called capacitance.
`C= "Q"/"V"`
SI unit of capacitor is farad.
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संबंधित प्रश्न
Draw a neat labelled diagram of a parallel plate capacitor completely filled with dielectric.
Explain briefly the process of charging a parallel plate capacitor when it is connected across a d.c. battery
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(i) electric field between the plates
(ii) capacitance, and
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Solve the following question.
A parallel plate capacitor is charged by a battery to a potential difference V. It is disconnected from the battery and then connected to another uncharged capacitor of the same capacitance. Calculate the ratio of the energy stored in the combination to the initial energy on the single capacitor.
For a one dimensional electric field, the correct relation of E and potential V is _________.
In a parallel plate capacitor, the capacity increases if ______.
A parallel plate capacitor is connected to a battery as shown in figure. Consider two situations:
- Key K is kept closed and plates of capacitors are moved apart using insulating handle.
- Key K is opened and plates of capacitors are moved apart using insulating handle.
Choose the correct option(s).
- In A: Q remains same but C changes.
- In B: V remains same but C changes.
- In A: V remains same and hence Q changes.
- In B: Q remains same and hence V changes.
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