Question

A single-turn circular loop of radius 14 cm is to produce a field at its center that will just cancel the earth's magnetic field at the equator, which is 0.7 g directed north. the permeability of free space is 4 π × 10−7 t · m/a. find the current in the loop. answer in units of a

Answer 1

49 A

Step-by-step explanation:

We are given that

Number of turns,N=1

Radius,r=14 cm=
`(14)/(100)=0.14 m`

1 m=100 cm

Magnetic field,B=0.7 G=
`0.7* 10^(-4) T`

`1G=10^(-4) T`

`\mu_0=4\pi* 10^(-7) Tm/A`

We know that magnetic field

`B=(\mu_0IN)/(2\pi r)`

Substitute the values

`0.7* 10^(-4)=(4\pi* 10^(-7)* 1* I)/(2\pi* 0.14)`

`I=(0.7* 10^(-4)* 2\pi* 0.14)/(4\pi* 10^(-7)* 1)`

`I=49A`