Question

When would an electromagnet stop working?
A.
An electromagnet would stop working after 24 hours.
B.
An electromagnet would stop working when it cools below 45°F.
C.
An electromagnet would stop working when the electric current is interrupted.
D.
An electromagnet would stop working when it gets sunlight.

Answer 1

C. An electromagnet stops working when the electric current is interrupted — its magnetic field exists only while current flows through the coil (e.g., if the circuit is opened or the power source is removed).