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The torque Vs armature current (14) graph for a DC series motor is
A) Parabola from no load to overload

B) Straight line

C) Parabola up to full load and straight lines at overloads

D) Rectangular hyperbola

A 200 KVA transformer has an iron loss of 1 KW and full load copper loss of 2 KW.
The KVA corresponding to maximum efficiency is
A) 200 KVA 8) 141.1 KVA C) 100 KVA D) 50 KVA

The all-day efficiency of the transformer depends on
A) Copper loss B) Amount of load
C) Duration of load D) Both B) and C)

A3 phase induction motor is running at a slip of 4% and input to the rotor is
2000 watts. The mechanical power developed in the rotor is
A) 1920 W B) 2000 W C) 1000 W D) 800 W

If the stator frequency and voltage of an induction motor are reduced proportionately,
then

A) Locked rotor current is reduced B) Torque developed is increased

C) Magnetising current is decreased D) Both A) and B)

In a squirrel cage induction motor, the starting torque with auto transformer starting
is times the torque with direct switching, K being the transformation
ratio of the auto transformer.

A) (2 B) 1/K ©) 1/2 D) K

The power factor of an alternator under short conditions is
A) Unity B) Almost zero lagging
C) Almost zero leading D) None of these

In 8 synchronous machine, the angle between the synchronously rotating stator flux
and rotor poles is called

A) Synchronizing angle B) Torque angle
C) Load angle D) Slip angle