Practice Question 5 Draw the free-body diagram for a magnet at rest on the side of a vertical refrigerator. The mass of the magnet is 0.01 kg, the magnetic force keeping the magnet in place is 1 N, and the coefficient of static friction between the magnet and the refrigerator is 0.1. Ff = 0.1N FN = 1N FM = 1N F= = 0.1 N Here, the normal force, out from the surface, is balancing the magnetic force. (It doesn't matter if you have the magnetic force on the left and the normal force on the right, since the question doesn't specify; the forces just have to be in opposite directions.) F ,=UFN=(0.1)(IN)=0.IN and F ,=mg=(0.01kg) (9.8mls')=0.1N The force that is keeping the magnet from sliding downward is not the normal force or the magnetic force but the frictional force