Question

The force between two parallel conductors, each of length $50cm$ and distant $20cm$ apart is $100$ N. If the current in one conductor is double that in another one then the values will respectively be(Given ${\mu }_0=4\pi \times {10}^{-7}$)

• A. ${10}^{4}A$ and $2\times {10}^{4}A$
• B. $50A$ and $100A$
• C. $10A$ and $20A$
• D. $5A$ and $10A$

Answer 1

The correct option is A ${10}^{4}A$ and $2\times {10}^{4}A$

$F=\frac{{\mu }_0{i}_1{i}_{2}l}{2\pi r}$
$100=\frac{2\times {10}^{-7}\times 2i\times 1\times \cdot 5}{\cdot 2}$
${10}^8=i^2$
$i={10}^{4}Amp$
Current in other wire $=2i=2\times {10}^{4}Amp$