Question

what is a solenoid?
I want the answer.

Answer 1

a cylindrical coil of wire acting as a magnet when carrying electric current.

Answer 2

Solenoid is a coil of many circular turns of insulated copper  wire in a shape of a cylinder that behaves as a magnet when current is passed through it.

The magnetic field in a solenoid is uniform and parallel

Here is the picture of a solenoid.

Hope This Helps You!