ELECTRICAL ENGINEERING OBJECTIVE TYPE QUESTIONS AND ANSWERS

1. Which of the following does not change in a transformer ?
(a) Frequency
(b) Voltage
(c) power
(d) auto set

Answer: (a) Frequency

2. No-load speed of which of the following motor will be highest ?
(a) Shunt motor
(b) Differentiate compound motor
(c) Cumulative compound motor
(d) Series motor
Answer: (d) Series motor

3. Laminations of core are generally made of
(a) Iron
(b) silicon steel
(c) carbon dioxide
(d) stainless steel particle

Answer: (b) silicon steel

4. In a transformer the energy is conveyed from primary to secondary
(a) by the flux
(b) through air
(c) through cooling coil
(d) Through the air tub

Answer:  (a) by the flux

5.  Which of the following could be lamina-proximately the thickness of laminations of a D.C. machine ?
(a) 0.005 mm
(b) 0.205 mm
(c) 5.5 m
(d) 0.5 m

Answer:  (d) 0.5 m

6. The direction of rotation of a D.C. series motor can be changed by
(a) interchanging supply terminals
(b) interchanging field terminal and supply terminal
(c) interchanging field terminals
(d) None of the above


Answer:  (c) interchanging field terminals

7. A transformer core is laminated to
(a) reduce eddy current losses
(b) reduce hysteresis loss
(c) reduce copper losses
(d) reduce power  losses

Answer:  (a) reduce eddy current losses

8. Which of the following application requires high starting torque ?
(a) machine starter
(b) Centrifugal pump
(c) Air blower
(d) Locomotive

Answer:  (d) Locomotive

9.  The field coils of D.C. generator are usually made of
(a) ethicon
(b) carbon
(c) cast iron/ steel
(d) copper

Answer:  (d) copper

10. If a D.C. motor is to be selected for conveyors, which miotor would be preferred ?
(a) Cumulative compound motor
(b) Shunt motor
(c) Series motor
(d) Differentially compound motor

Answer:  (c) Series motor

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