Question

You are given 13.0 mm of thin wire. You form the wire into a circular coil with 40 turns.

If this coil is placed with its axis parallel to a 0.19 TT magnetic field, what is the flux through the coil?

Express your answer with the appropriate units.

Answer 1

If length of thin wire is in 'mm', and not 'm' then let me know.

Magnetic flux through a coil placed in magnetic field is given by:

= N*(B.A) = N*B*A*cos

B = Magnetic field = 0.19 T

N = number of turns = 40

= Angle between magnetic field and area vector = 0 deg

A = Area of each coil = pi*r^2

r = radius of each coil

We know that total length of wire = 13.0 m (I'm assuming that unit of length of wire is 'm' and not 'mm', as may be you've mistyped your unit twice just like 0.19 'TT' if it's mm do let me know.)

Circumference of loop = C = N*2*pi*r

r = C/(2*pi*N) = 13.0/(2*pi*40)

A = pi*(13.0/(2*pi*40))^2

So,

= 40*0.19*pi*(13.0/(2*pi*40))^2*cos 0 deg

= 6.39*10^-2 Wb

Let me know if you've any query.