A sectional view of a cylindrical iron-clad plunger magnet is shown in Figure P12.1.8. The small air gap between the sides of the plunger and the iron shell is uniform and 0.25 mm long. Neglect leakage and fringing, and consider the iron to be infinitely permeable. The coil has 1000 turns and carries a direct current of 3 A. Compute the pull on the plunger for g = 1.25 cm.
