Physics

Problem

A horizontal wire of length

1.0\,\text{m}

has a mass per unit length of

50\,\text{g}\,\text{m}^{-1}

. It is placed in a vertical uniform magnetic field of

0.20\,\text{T}

with its length perpendicular to the field. What current should be passed through the wire so that the magnetic force just balances its weight?

g = 9.8\,\text{m}\,\text{s}^{-2}

. a)

0.245\,\text{A}

24.5\,\text{A}

2.45\,\text{A}

4.90\,\text{A}