Question

Consider two parallel straight wires carrying electric current in opposite directions with the same magnitude of 2.0 A. The center-tocenter distance between the two wires is 5.0 mm. One wire is infinitively long and the other wire is 0.30 m long. Is the magnetic force between the two wires repulsive or attractive? What is the magnitude of the magnetic force between them? (Answer: ????????=4.8×10−5 ????????)

Answer 1

Both wires repels to each other and magnitude of the magnetic force between them is
`4.8 * 10^(-5)` N

Step-by-step explanation:

Given:

Current
`I =2` A

Length of wire
`l = 0.30` m

Separation between two wire
`a = 5 * 10^(-3)` m

Here current is in opposite direction so both wires repels to each other.

Force in current carrying wire is given by,

`F = (\mu_(o) I^(2) l )/(2\pi a)`

Where
`\mu_(o) = 4\pi * 10^(-7)`

`F = (4\pi * 10^(-7) * (2)^(2) * 0.3 )/(2\pi * 5 * 10^(-3) )`

`F = 4.8 * 10^(-5)` N

Therefore, both wires repels to each other and magnitude of the magnetic force between them is
`4.8 * 10^(-5)` N