Question

Two kinds of magnets are shown below.



Cameron works in a junkyard, and he needs a machine that can lift scrap metal and then let go of it. Which type of magnet does Cameron need, and why?
A.
Cameron needs a magnet like magnet 1 because it can pick up all materials.
B.
Cameron needs a magnet like magnet 1 because it can be turned on and off.
C.
Cameron needs a magnet like magnet 2 because it does not need electricity.
D.
Cameron needs a magnet like magnet 2 because it is stronger than magnet 1.

Answer 1

B. Cameron needs a magnet like magnet 1 because it can be turned on and off. An electromagnet can be energized to pick up metal and de-energized to release it; a permanent magnet cannot be switched off.