Question

Hiro wants to model the magnetic field of a bar magnet using a shoe box and pipe cleaners. He labels the ends of the shoe box N and S.

How should he position the pipe cleaners? Check all that apply.

They should exit the box at N and enter at S.
They should exit the box at S and enter at N.
They should be put inside the box so the two ends join.
None should be put inside the box.
They should form loops outside of the box over the top, bottom, and sides of the box.
They should form loops outside of the box, but over only the sides of the box.

Answer 1

Select:
- They should exit the box at N and enter at S.
- They should be put inside the box so the two ends join.
- They should form loops outside of the box over the top, bottom, and sides of the box.

Reason: magnetic field lines leave the north pole and enter the south pole outside the magnet, then continue inside the magnet from S back to N, so the field lines are continuous closed loops that pass out of N, around the outside, into S, and through the interior.