ELECTRICAL ENGINEERING QUESTIONS WITH ANSWER

Question No. 3521.  For power factor correction, synchronous motors operate at
(a) normal load with zero excitation
(b) no-load and under-excited fields
(c) normal load with minimum excitation
(d) no-load and greatly over-excited fields

Answer: (d) no-load and greatly over-excited fields

Question No. 3522.  The field coils of D.C. generator are usually made of
(a)  copper
(b) mica
(c) cast iron
(d) carbon

Answer: (a)  copper

Question No. 3523. An amplidyne can give which of the following characteristics ?
(a) Constant current
(b) Constant current, constant voltage and constant power
(c) Constant current as well as constant voltage

(d) Constant voltage
(e) None of the above

Answer: (b) Constant current, constant voltage and constant power

Question No. 3524. directly converts temperature into voltage.
(a) Gear train
(b) Potentiometer
(c) Thermocouple
(d) LVDT
(e) None of the above

Answer: (c) Thermocouple

Question No. 3525. The maximum power developed in a synchronous motor will depend on
(a) the rotor excitation only
(b) the rotor excitation, supply voltage and maximum value of coupling angle (90°)
(c) the rotor excitation and supply volt-age both
(d) the supply voltage only
(e) none of the above

Answer: (b) the rotor excitation, supply voltage and maximum value of coupling angle (90°)

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