1) Write down the equation for energy density for magnetic circuit.
2) Write down the factors on which hysteresis loss depends.
3) What do you mean by a core loss? Write down its significance in electric machines?
4) What do you mean by eddy current loss?
5) Describe How are hysteresis and eddy current losses minimized?
6) Describe in detail about magnetization curve of Ferro –magnetic material.
7) Deduce the relation between mutual inductance and self inductances of two Magnetically coupled coils.
8)(a) Describe AC operation of magnetic circuits in detail.
(b) Describe about hysteresis and eddy current losses in detail.
9)(a) Write in detail about magnetically induced emf and force and deduce the appropriate Expression.
(b) The electromagnetic relay has the exciting coil of 800 turns. Coil has cross section of 5 cm x 5cm . Determine:
1. Coil inductance if air gap length is 0.5 cm.
2. Field energy stored for a coil current of 1.25 A
3. Permeance at air gap
10) Describe about three basic rotating electric machine types in detail.