Two strong magnets on opposite sides of a small table are shown. The long-range attractive force between the magnets keeps the lower magnet in place. Suppose the weight of the table is 26.7 N, the weight of each magnet is 6.55 N, and the magnetic force on the lower magnet is 2.16 times its weight.

Question

A)What is the magnitude of the normal force of the table on the upper magnet?

B)What is the magnitude of the normal force of the table on the lower magnet?

C)What is the normal force of the ground on the table?

... I tried balancing the vertical forces in each scenario to solve for the normal force but I'm not getting the right answer.

For the upper magnet, I had the normal force of the table (up), the weight of the magnet mg (down) and the magnetic force of the lower magnet (down)

For the lower magnet I had the same forces but the normal force and the magnetic forces switched direction

For the table I had, the weights of the table and the two magnets being exerted down

... Am I missing something?

Answer 1

you are right on the ground force (table+2magnets).

The normal force on the table is the magnet weight +magnetic force.

The normal force of the table on the lower magnet is magnetic force- magnet weight.

Answer 2

Okay, I get it now. Thanks Bob