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Question
A circular coil of wire is made up of 200 turns, each of radius 10 cm. If a current of 0.5A passes through it, what will be the Magnetic field at the centre of the coil?
Solution
Given:
N = 200 turns
R = 10 cm = 10 × 10−2 m = 1 × 10−1 m
I = 0.5 A = 5 × 10−1 A
To find:
Magnetic field (B) at center of coil = ?
Formula:
`B_("center") = (mu_0 NI)/(2 R)`
∴ `B_("center") = (4 pi xx 10^-7 xx 200 xx 5 xx 10^-1)/(2 xx 1 xx 10^-1`
= 4 × 3.142 × 10−7 × 500
= 4 × 3.142 × 5 × 10−5
= 62.84 4 × 10−5
Bcenter = 6.284 × 10−4 Wb/m2
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