Question

the images below show two pairs of magnets. the magnets in different pairs do not affect each other. all the magnets shown are made of the same material, but some of them are different sizes.
pair 1 pair 2
n s s n s n n s
38.3 mm 38.3 mm
think about the magnetic force between the magnets in each pair. which of the following statements is true?
the magnitude of the magnetic force is greater in pair 1.
the magnitude of the magnetic force is greater in pair 2.
the magnitude of the magnetic force is the same in both pairs.

Explanation:

Step1: Determine magnetic - force factors

The magnetic force between two magnets depends on the magnetic properties of the material, the distance between them, and their magnetic moments. Here, the magnets are of the same material and the distance between the pairs of magnets is the same ($d = 38.3\ mm$).

Step2: Analyze magnetic - moment and distance

Since the material is the same and the distance is equal, and there is no information suggesting different magnetic - moment due to size (and assuming no other external factors), the magnetic force between the pairs of magnets is determined only by these two factors which are equal for both pairs.

Answer:

The magnitude of the magnetic force is the same in both pairs.