which of the following changes made the weakest electromagnet?

Question

(1 point)

a. Using a plastic core instead of an iron core

b. Using 3 batteries instead of 5

c. Using a small core instead of a large core

d. Use 3 coils instead of 9

Answer 1

The option that would make the weakest electromagnet is:

a. Using a plastic core instead of an iron core.

Plastic is a non-magnetic material and does not enhance the magnetic field, while iron is a ferromagnetic material that significantly increases the strength of the electromagnet. The other options (using fewer batteries, a smaller core, or fewer coils) would also weaken the electromagnet, but using a plastic core fundamentally means losing the core's ability to amplify the magnetic field.