Question

Which feature of electromagnets makes them more useful than permanent

magnets in many modern technologies?
A. Electromagnets are not dependent on a power supply.
B. The strength of the magnetic field is more consistent in
electromagnets.
C. Electromagnets cannot be turned on and off.
D. The current can be adjusted to control the strength of the
magnetic field.

Answer 1

The current can be adjusted to control the strength of the

magnetic field.