Question

Two parallel wires in free spaces are `10cm` apart and each carries a current of `10A` in the same direction. The force one wire exerts on the other per metre of length is
A. `2xx10^(-4)N` , attractive
B. `2xx10^(-4)N` ,repulsive
C. `2xx10^(-7)N` ,attractive
D. `2xx10^(-7)N` ,repulsive

Answer 1

Correct Answer - A
`F=(mu_(0))/(4pi)(2i_(1)i_(2))/(a)=10^(-7)xx(2xx10xx10)/(0.1)=2xx10^(-4)N`
Direction of current is same, so force is attractive.