Question

Two parallel straight conductors carrying currents 5A each repel other with a force of $25\times {10}^{-5}N{m}^{-1}$. The distance between the conductors is

• A. 4 cm
• B. 0.4 cm
• C. 2 cm
• D. 0.2 cm

Answer 1

The correct option is C 2 cm

$\begin{array}{c}\frac{\mu oi}{2\pi d}=25\times {10}^{-5}\\ \Rightarrow \frac{4\pi \times {10}^{-7}\times 25}{2\pi d}=25\times {10}^{-5}\\ \Rightarrow d=\frac{2\times {10}^{-7}}{{10}^{-5}}m\\ =2m\end{array}$

$\therefore$ Option $C$ is correct.