For the cylindrical iron-clad solenoid magnet of Fig. 4.9, assume that the magnetic path reluctance remains constant at a value corresponding to the linear part of the magnetization curve.
(a) Derive an expression for the force in terms of g for constant coil current 2.25 A. Calculate the value of the force for g = 1 and 0.2 cm.
(b) What is the electrical energy input to the system when g changes from 1 to 0.2 cm, while the coil current is maintained constant at 2.25 A.
(c) Calculate the work done on the plunger during the movement specified in part (b).
(d) With the coil current maintained constant at 2.25 A. What is the direction and magnitude of the electrical energy flow if the plunger is made to move from g = 0.2 to 1 cm?
