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a semicircle wire of radius R is rotated...

a semicircle wire of radius `R` is rotated with constant angular velocity about an axis passing through one end and perpendicular to the plane of wire. There is a uniform magnetic field of strength `B`. The induced emf between the ends is

A

`B omega R^(2)//2`

B

`2 B omega R^(2)`

C

is variable

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
B
Here effective length is `2R`
`epsilon=1/2Bomega(2R)^(2)=2BomegaR^(2)`
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RESONANCE ENGLISH-ELECTROMAGNETIC INDUCTION-Exercis-1 PART 2
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  4. The following figure a conducting disc rotating about its axis in a pe...

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