Two long parallel copper wires carrying currents in the opposite directions of 5 A each. If the wires are separated by a distance of 0.5 m, then the force per unit length between the two wires is

Options

A. `10^(-5) N` attractice force
B. `10^(-5) `N nepulsive force
C. `2xx10^(-5)` N attractive force
D. `2xx10^(-5) `N repulsive force

Answer

B

Explanation

Force between two wires,
`F=(mu_(0)i)/(2pi)(i_(1)i_(2))/(r)=(4pixx10^(-7)xx5xx5)/(2pixx0.5)=2xx10^(-7)xx5xx10`
=`10^(-5) N` repulsive force