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The capacitance of a variable radio capa...

The capacitance of a variable radio capacitor can be changed from `50pF` to `200pF` by turning the dial from `0^(@)` to `180^(@)`. With the dial set at `180^(@)`, the capacitor is connected to a `400V` battery. After charging, the capacitor is disconnected from the battery and dial is tuned at `0^(@)`?
(a) what is the `p.d.` across the capacitor when dial reads `0^(@)`?
(b) how much work is required to turn the dial, if friction is neglected?

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DC PANDEY-ELECTROSTATIC POTENTIAL AND CAPACITORS-(C) Chapter exercises
  1. The capacitance of a variable radio capacitor can be changed from 50pF...

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  2. A capacitor of 2 muF is charged as shown in the figure. When the switc...

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  3. A parallel plate capacitor of area A, plate separation d and capacitan...

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  4. A parallel plate air capacitor of capacitance C is connected to a cell...

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  5. Calculate the charge on equivalent capacitance of the combination show...

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  6. An isolated sphere has a capacitance of 50 pF. (a) Calculate its radiu...

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  7. A parallel plate capacitor has 91 plates, all are identical and arrang...

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  8. A particle of mass 1.96xx10^(-15) kg is kept in equilibrium between tw...

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  9. The distance of the closest approach of an alpha particle fired at a n...

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  10. A uniform electric field E is created between two parallel charged pla...

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  11. A battery charges a parallel plate capacitor of thickness (d) so that ...

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  12. A capacitor of capacitance 100(mu)F is charged by connecting it to a b...

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  13. An infinite number of identical capacitors each of capacitance 1 mF ar...

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  14. A parallel plate capacitor is charged and then isolated. The effect of...

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  15. A spherical shell of radius 10 cm is carrying a charge q. If the elect...

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  16. An electron of mass m(e ) initially at rest moves through a certain di...

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  17. Consider the diagram, A parallel plate capacitor has the plate wi...

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  18. A conducting sphere of radius R is given a charge Q. The electric pote...

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  19. Two concentric spheres kept in air have radii R and r. They have simil...

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  20. Two charges of equal magnitude q are placed in air at a distance 2a ap...

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  21. Consider two concentric spherical metal shells of radii r(1) and r(2) ...

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