A mechanic dropped a bolt he needed to repair a car motor. He decided to make a simple electromagnet to try to attract the metal bolt. Which list of material would make the best electromagnet?

Question

a
wooden rod for a core, copper wire, 9-volt battery
b
plastic rod for a core, copper wire, 9-volt battery
c
metal rod for a core, copper wire, 9-volt battery
d
glass rod for a core, copper wire, 9-volt battery

Answer 1

The best choice for making a simple electromagnet from the given options is:

c) metal rod for a core, copper wire, 9-volt battery

A metal rod, particularly one made of iron or a similar ferromagnetic material, will greatly enhance the strength of the electromagnet compared to non-metal cores like wood, plastic, or glass. The copper wire is needed to create the magnetic field when electric current flows through it, and the 9-volt battery provides the necessary power.