The extremely high input impedance of a MOSFET is Primarily because of

(A) Absence of its channel
(B) Depletion of current carriers
(C) Extremely small leakage current of its gate capacitor
(D) Negative VGS

The crawling in an induction motor is caused by

(A) Improper design of the machine
(B) Low voltage supply.
(C) High loads.
(D) Harmonics developed in the motor.

The “Superposition theorem” is essentially based on the concept of

(A) duality.
(B) linearity.
 (C) reciprocity.
 (D) non-linearity.

The magnetizing current in a transformer is rich in

1. Third harmonics
2. Fifth harmonics
3. Seventh harmonics
4. Thirteen harmonics

An auto-transformer having a transformation ratio of 0.8 supplies a load of 3kW. The power transferred conductively from primary to secondary is

1. 0.6 kW
2. 2.4 kW
3. 1.5 kW
4. 0.27 kW

While performing the open-circuit and short-circuit tests on a transformer to determine its parameters the status of the low voltage (L.V) and high voltage (H.V) will be such that

1. In Open circuit L.V is open and in short circuit H.V is shorted
2. In Open circuit H.V is open and in short circuit L.V is shorted
3. In Open circuit L.V is open and in short circuit L.V is shorted
4. In Open circuit H.V is open and in short circuit H.V is shorted

If a sinusoidal voltage source is connected to a power transformer, its no-load current would be

1. Sinusoidal and lagging the voltage by ninety degrees
2. Sinusoidal and lagging the voltage by less than ninety degrees
3. Rich in third harmonic and its fundamental would lag the voltage by ninety degrees
4. Rich in third harmonic and its fundamental would lag the voltage less than ninety degrees