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Question
A circular coil of cross-sectional area 200 cm2 and 20 turns is rotated about the vertical diameter with angular speed of 50 rad s−1 in a uniform magnetic field of magnitude 3.0 × 10−2T. Calculate the maximum value of the current in the coil.
Solution
Here, A = 200 cm2
N=20
ω = 50 rad/s
B = 3.0× 10−2 T
for maximum current emf induced should be maximum.
So, for maximum emf sinωt in e = NAB ω sinωt should be 1.
Hence, e = NABω
`e = 20 × 200/10000 × 50 × 3 × 10^-2 `
`e= 0.6 V`
Since, resistance of the circular loop is not given, let us consider its resistance to be R.
Therefore, current I in the coil is
`I = 0.6/R A`
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