Question

Through two parallel wires A and B, 10A and 2A of currents are passed respectively in opposite directions. If the wire A is infinitely long and the length of the wire B is 2m, then force on the conductor B, which is situated at 10 cm distance from A, will be:

Options

• 8 × 10⁻⁷ N

• 8 × 10⁻⁵ N

• 4 × 10⁻⁷ N

• 4 × 10⁻⁵ N

Answer 1

8 × 10⁻⁵ N

Explanation:

F = `μ_0/(4π) (2"I"_1"I"_2)/"r" xx ℓ`

= `(10^-7 xx 2 xx 10 xx 2)/(0.1) xx 2`

= 8 × 10⁻⁵ N