A constant current is sent through a helical coil. The coil:
A) tends to get shorter
B) tends to get longer
C) tends to rotate about its axis
D) produces zero magnetic field at its center
E) none of the above

Question

Quizplus · Accepted Answer

When a constant current is sent through a helical coil, the coil tends to get shorter due to the magnetic field created by the current. This field exerts a force on different parts of the coil, pulling the turns of the coil closer together.

A Constant Current Is Sent Through a Helical Coil