Question

A copper wire of length 16 cm is in a magnetic field of 0.19 T. If it has a mass of 9.0 g, what is the minimum current through the wire that would cause a magnetic force equal to its weight?

Answer 1

2.9 A

Step-by-step explanation:

L = 16 cm = 0.16 m

B = 0.19 T

m = 9 g = 0.009 kg

Let the minimum current be i.

Magnetic force is balanced by the gravitational force

B x i x L = m x g

0.19 x i x 0.16 = 0.009 x 9.8

i = 2.9 A