Question 234: Magnetism and Matter

Question

A horizontal overhead powerline is at height of $$4m$$ from the ground and carries a current of $$100A$$ from east to west. The magnetic field directly below it on the ground is 
$$\left( {{\mu _0} = 4\pi  	imes {{10}^{ - 7}}\,\,Tm\,\,{A^{ - 1}}} ight)$$

Accepted Answer

The magnetic field is
$$B = {{{\mu _0}} \over {4\pi }}{{2I} \over r}$$
$$ = {10^{ - 7}} 	imes {{2 	imes 100} \over 4}$$
$$ = 5 	imes {10^{ - 6}}T$$
According to right hand palm rule, the magnetic field is directed towards south.

Answer

$$2.5 	imes {10^{ - 7}}\,T$$ southward

Answer

$$5 	imes {10^{ - 6}}\,T$$ northward

Answer

$$5 	imes {10^{ - 6}}\,T$$ southward

Answer

$$2.5 	imes {10^{ - 7}}\,T$$ northward

Magnetism and Matter

A horizontal overhead powerline is at height of $4m from the ground and carries a current of 100A from east to west. The magnetic field directly below it on the ground is \left( {{\mu _0} = 4\pi \times {{10}^{ - 7}}\,\,Tm\,\,{A^{ - 1}}} \right)

Choose the correct answer: