Question

Through two parallel wires x and y, currents of 10A and 2A, respectively are passed in opposite directions. X is infinitely long and y has a length of 2m. The distance between them is 10cm. The magnetic force on y is

• A. $4\times {10}^{-5}N$
• B. $4\times {10}^{-6}N$
• C. $8\times {10}^{-5}N$
• D. $8\times {10}^{-6}N$

Answer 1

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

$F=\frac{{\mu }_{0}i,i_{2}l}{2\pi r}=\frac{2\times {10}^{-7}\times 10\times 2\times 2}{10\times {10}^{-2}}F=8\times {10}^{-5}N$