Chapter 7.2, Problem 13R

To determine

The change in an electromagnet’s magnetic field if the iron core is replaced by an aluminium core.

Explanation of Solution

Introduction: An electromagnet is a temporary magnet created when a current carrying wire wrapped around an iron core.

An electromagnet behaves like other magnets when there is current in the solenoid.

The electromagnet’s one end is a north pole, and the other end is south pole. When placed in a magnetic field, an electromagnet will align itself in the direction of the magnetic field lines. An electromagnet will also exert a magnetic force on other magnets.

All magnets are metals, but not all metals are magnets.

Aluminium not being a magnet weakens the electromagnet’s magnetic field, if the iron core is replaced by it.

The magnetic field will be only due to the wire looped around the solenoid.

Conclusion: The electromagnet’s magnetic field decreases if the iron core is replaced by an aluminium core.