A long wire is wound in a circular coil of a radius of 1 meter. The coil consist of 70 loops of the wire are around it. What is the length of the wire to form the coil

Answer:A long wire wound in the form of a helical coil is known as a solenoid ... (Figure) shows a solenoid consisting of N turns of wire tightly wound over a length L. A ... Outside the solenoid, one can draw an Ampère's law loop around the entire ... Therefore, for locations outside of the solenoid's radius, the magnetic field is zero.