Question

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

• A. $6\times {10}^{-5}$N
• B. $9\times {10}^{-5}$N
• C. $8\times {10}^{-5}$N
• D. $10\times {10}^{-5}$N

Answer 1

The correct option is C $8\times {10}^{-5}$N

Force on conductor b,

$F=\frac{{\mu }_0{I}_a{I}_b}{2\pi d}\times {\ell }_b$

$F=2\times {10}^{-7}\times 10\times 2\times 10\times 2=8\times {10}^{-5}$

Option $\text{C}$ is the correct answer.