Question

a long wire carries a steady current

Answer 1

Hey!

It seems its incomplete:

Qn ---> A long wire carries a steady current. It is bent into a circle of one turn and the magnetic field at the centre of the coil is B. It is then bent into a circular loop of n turns. The magnetic field at the centre of the coil will be:

Ans---> n^2

See the attachment. 

Good day!

Answer 2

$\huge\pink{Ello \: ♡}$

A current of electricity is a steady flow of electrons. When electrons move from one place to another, round a circuit, they carry electrical energy from place to place like marching ants carrying leaves. Instead of carrying leaves, electrons carry a tiny amount of electric charge.