Question

Two long, straight wires both carry current to the right, are parallel, and are 25 cm apart. Wire one carries a current of 2.0 A and wire two carries a current of 5.0 A. How far from wire 1 is the net magnetic field equal to 0?

Answer 1

x = 7.14 meters

Step-by-step explanation:

It is given that,

Current in wire 1,
`I_1=2\ A`

Current in wire 2,
`I_2=5\ A`

Distance between parallel wires, r = 25 cm

Let at P point the net magnetic field equal to 0. The magnetic field at a point midway between the is given by :

`B=(\mu_oI)/(2\pi r)`

Let the distance is x from wire 1. So,

`(I_1)/(r)=(I_2)/((0.25-r))`

`(2)/(r)=(5)/((25-r))`

`x=(50)/(7)\ m`

x = 7.14 meters

So, the magnetic field will be 0 at a distance of 7.14 meters from wire 1. Hence, this is the required solution.