Question 302: Magnetism and Matter

Question

A galvanometer coil has 500 turns and each turn has an average area of 3 $$ 	imes $$ 10–4 m2
. If a torque of
1.5 Nm is required to keep this coil parallel to a magnetic field when a current of 0.5 A is flowing
through it, the strength of the field (in T) is ______.

Accepted Answer

Given N = 500
A = 3 $$ 	imes $$ 10
Ã¢ÂÂ4
m
2
$$	au $$ = 1.5 Nm
i = 0.5 A
We know, $$	au  = BINA\,sin	heta $$
$$1.5 = B 	imes 0.5 	imes 500 	imes 3 	imes {10^{ - 4}}$$
$$B = {{10000} \over {500}} = 20$$ Tesla

Magnetism and Matter

A galvanometer coil has 500 turns and each turn has an average area of 3 $ \times $ 10–4 m2 . If a torque of 1.5 Nm is required to keep this coil parallel to a magnetic field when a current of 0.5 A is flowing through it, the strength of the field (in T) is ______.

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