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Questions
A toroid of a central radius of 10 cm has windings of 1000 turns. For a magnetic field of 5 × 10-2 T along its central axis, what current is required to be passed through its windings?
A toroid of narrow radius of 10 cm has 1000 turns of wire. For a magnetic field of 5 × 10-2 T along its axis, how much current is required to be passed through the wire?
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Solution
Data: Central radius, r = 10 cm= 0.1 m, N = 1000,
B = 5 × 10-2 T, µ0 = 4π × 10-7 T·m/A
The magnetic induction,
B = `(mu_0"NI")/(2pi"r") = mu_0/(4pi) (2"NI")/"r"`
∴ `5 xx 10^-2 = 10^-7 xx (2(1000)"I")/0.1`
∴ l = `50/2 = 25` A
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