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Question
Calculate magnetic flux density of the magnetic field at the centre of a circular coil of 50 turns, having a radius of 0.5m and carrying a current of 5 A.
Solution
N = 50 turns, Radius r = 0.5 m, Current I = 5 A
∴ Magnetic flux density at centre = B =`(mu_0NI)/(2a)`
=`(4pi xx10^-7 xx 50xx5)/(2xx0.5) T`
=`2pi xx 10^-7 xx 500 T`
B = 3.14 × 10-4 T
or B = 10-4 π T
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