A Metal Rod Rotates About One of Its Ends Perpendicular to a Plane Whose Magnetic Induction is 4 X 10-3 T. - Physics

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A metal rod `1/sqrtpi `m long rotates about one of its ends perpendicular to a plane whose magnetic induction is 4 x 10-3 T. Calculate the number of revolutions made by the rod per second if the e.m.f. induced between the ends of the rod is 16 mV.

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Solution

`L=1/sqrtpim="radius"`

B = 4x10-3T

e = 16mv

=16x10-3v

Area covered in one revolution

A=πL2

`=pi(1/sqrtpi)^2`

=1m2

e=BfA

`:.f=e/(BA)`

`=(16xx10^(-3))/(4xx10^(-3)xx1)`

f=4Hz

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2013-2014 (March)

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