Practice Test: Question Set - 01
1. A three point starter is considered suitable for
- (A) Shunt motors
- (B) Shunt as well as compound motors
- (C) Shunt, compound and series motors
- (D) All D.C. motors
2. Which D.C. motor has got maximum self loading property?
- (A) Series motor
- (B) Shunt motor
- (C) Cumulatively compounded motor
- (D) Differentially compounded motor
3. Sparking at the commutator of a D.C. motor may result in
- (A) Damage to commutator segments
- (B) Damage to commutator insulation
- (C) Increased power consumption
- (D) All of the above
4. Following motor is used where high starting torque and wide speed range control is required.
- (A) Single phase capacitor start
- (B) Induction motor
- (C) Synchronous motor
- (D) D.C. motor
5. The armature voltage control of D.C. motor provides
- (A) Constant torque drive
- (B) Constant voltage drive
- (C) Constant current drive
- (D) None of the above
6. Which one of the following is not necessarily the advantage of D.C. motors over A.C. motors?
- (A) Low cost
- (B) Wide speed range
- (C) Stability
- (D) High starting torque
7. If a D.C. motor designed for 40°C ambient temperature is to be used for 50°C ambient temperature, then the motor
- (A) Of lower H.P. should be selected
- (B) Of higher H.P. should be selected
- (C) Can be used for 50°C ambient temperature also
- (D) Is to be de-rated by a factor recommended by
manufacturer and select the next higher H.P. motor
8. Which motor should not be started on no-load?
- (A) Series motor
- (B) Shunt motor
- (C) Cumulatively compounded motor
- (D) Differentially compounded motor
9. The losses occurring in a D.C. generator are given below. Which loss is likely to have highest proportion at rated load of the generator?
- (A) Hysteresis loss
- (B) Field copper loss
- (C) Armature copper loss
- (D) Eddy current loss
10. Which of the following losses are significantly reduced by laminating the core of a D.C. generator?
- (A) Hysteresis losses
- (B) Eddy current losses
- (C) Copper losses
- (D) Windage losses