Question

The force on a wire carrying 22.0 A is a maximum of 4.06 N when placed between the pole faces of a magnet. If the pole faces are 19.5 cm in diameter, what is the approximate strength of the magnetic field?

--- T

Answer 1

The expression to be used to find the force acting on a current carrying conductor kept in a magnetic field is given as F = B i l sin @

=> B = F/il sin @

B- magnetic field induction in tesla

i- the current in ampere

l - the length of the wire subjected to magnetic field

@ - the angle between the magnetic field vector and current element vector.

In your problem, @ is 90 as the force is said to be maximum.

For l, we have to take it to be 0.195 m assuming that the magnetic lines come out all along from the cross sectional face of poles.

Hence plugging and solving for B we get, B = 0.9464 T