Two parallel, long wires are kept 0 . 20 m apart in vacuum, each carrying current of x A in the same direction. If the force of attraction per meter of each wire is 2 × 10 - 6 N , then the value of x

Question

Two parallel, long wires are kept 0 . 20 m apart in vacuum, each carrying current of x A in the same direction. If the force of attraction per meter of each wire is 2 × 10 - 6 N , then the value of x is approximately

TestHub · Accepted Answer

Force per unit length between two parallel wires is $\frac{F}{l} = \frac{μ_{0} i_{1} i_{2}}{2 π d}$

Here, $i_{1} = i_{2} = i$ and $\frac{F}{l} = 2 \times 10^{- 6} N$

Then, $2 \times 10^{- 6} = \frac{4 π^{2} \times 10^{- 7} i^{2}}{2 π \times 0.2}$

$\Rightarrow i^{2} = \sqrt{2} \Rightarrow i = 1.4 A$

Hence, $x = 1.4$ .

Physics - Magnetism Question with Solution | TestHub

Options:

Doubts & Discussion