Explanation:
It is given that,
Current in wire 1, I₁ = 10 A
Current in wire 2, I₂ = 20 A
Distance between wires, d = 10 cm = 0.1 m
Force per unit length is given by :
So, the magnetic force acting per unit length of the wires 
. Since, the current is in same direction. So, the force is attractive in nature.
So if the formula for work is force times displacement times cosine(theta), you'd plug in the numbers
100x5 (since there's no angle in the problem, cosine(theta) isn't used
100x5 = 500
So the answer would be B.
Hope that helps!
When a plane travels 395,000 meters in 9,000 seconds its speed is 395,000 ÷ 9000 = 43.888888 (the 8 repeats) meters per second.
