Question

To draw the bh curve of fe using solenoid and determine energy loss from hysteresis.Practical

Answer 1

Initially the material is unmagnitised . Now we place solenoid and increase current through it . Magnetic field in material increases and saturates ( curve oa of the fig).

Now we decrease i and reduce it to zero. At this point B should be zero but its not so because of retentivity ,Curve ae of the fig.Now current in solenoid is sent in the reverse direction. B in material Now magnetising intensity we need to apply to make B zero (i.e curve oc ) is called coercivity decreases to zero.