Question

"Two long parallel wires 24.0 cm apart carry currents of 3.0 A and 8.0 A in the same direction. How far from the wire carrying 3.0 A is the magnetic field is zero (in cm)?"

Answer 1

6.5454 m

Step-by-step explanation:

Let the distance from the wire carrying 3 A current is x

Then the distance from the the carrying current 8 A is 24-x

We know that magnetic field due to long wire is given by
`B=(\mu _0i)/(2\pi r)`

It is given that magnetic field is zero at some distance so

`(\mu _0i_1)/(2\pi x)=(\mu _0i_2)/(2\pi (24-x))`

Here
`i_1=3\ A \ and\  i_2=8\ A`

So
`(3)/(x)=(8)/(24-x)=6.5454\ m`