Question

Alisha made the electromagnet shown below. She used the electromagnet to pick up some paper clips.



Alisha wants the electromagnet to be able to pick up even more paper clips. What should she change?
A.
She should move the nail farther from the paper clips.
B.
She should move the battery to the other side of the nail.
C.
She should add more loops of wire around the nail.
D.
She should use bigger paper clips.

Answer 1

C. She should add more loops of wire around the nail.

More loops increase the magnetic field strength of the electromagnet (for the same current), so it can pick up more paper clips. Moving the nail farther would weaken the field, changing the battery position doesn't increase strength (it only can reverse polarity), and bigger paper clips would be harder to pick up.