Question

A solenoid is built with 870 turns uniformly distributed over a length of 0.390 m to produce a magnetic field of magnitude 1.00 × 10−4 T at its center. What is current necessary for this to happen? 17.4 mA 35.7 mA 74.9 mA

Answer 1

Answer:

35.7mA

Explanation:

B= μnI

μ: permeability of free space 4π× 10^-7

n: number of turns per unit length

I: current through the coil

B: magnetic field

1.00 × 10−4= 4π× 10^-7 × 870/0.39×I

I= 35.7mA