Q. In Nebraska the horizontal component of earth’s field is 0.2 G. If a vertical wire carries a current of 30 A upward there. What is the magnitude and direction of the force on 1 m of wire? (1 G = $10^{- 4}$ T)
A) 6 E to W
B) $6\ \times 10^{- 3}\ $E to W
C) $6\ \times 10^{- 3}\ $E to W
D) $6\ \times 10^{- 4}\ $E to W
Explanation
(d) $F = Bil = \left( 0.2 \times 10^{- 4} \right) \times 30 \times 1$
= 6 $\times 10^{- 4}\ $east to west.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.