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A variable air capacitor used in radio t...

A variable air capacitor used in radio tuning circuit is made of N semi-cireuler plates each of radius R and positioned a distance d from its neighboring plates. A second set of similar plates is enmeshed with its plates half-way between those of first set. Second set of plates can rotate as a complete unit. capacitance of arrangement is

A

`(Nepsilon_0(pi-theta)R^2)/d`

B

`((N-1)epsilon_0(pi-theta)R^2)/d`

C

`((N-2)epsilon_0(pi-theta)R^2)/d`

D

`((2N-1)epsilon_0(pi-theta)R^2)/d`

Text Solution

Verified by Experts

The correct Answer is:
D
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