Electrical Engineering Question Answers

Question No. 1. A potentiometer may be used for
(a) measurement of resistance
(b) measurement of current
(c) calibration of ammeter
(d) calibration of voltmeter
(e) all of the above
Answer: (e) all of the above

Question No. 2. A dc shunt generator has a speed of 800 rpm when delivering 20 A to the load at the
terminal voltage of 220V. If the same machine is run as a motor it takes a line
current of 20A from 220V supply. The speed of the machine as a motor will be
(A) 800 rpm.
(B) more than 1000 rpm.
(C) less than 800 rpm.
(D) both higher or lower than 800 rpm.
Answer: (C) less than 800 rpm.

Question No. 3. In order to reduce the harmonics in the emf generated in an alternator

(A) slots are skewed
(B) salient pole tips are chamfered
(C) winding is well distributed
(D) all of the above.

Answer: (D) all of the above.

Question No. 4. The use of _____ instruments is merely confined within laboratories as stand¬ardizing
instruments.
(a) absolute
(b) indicating
(c) recording
(d) integrating
(e) none of the above
Answer: (a) absolute



Question No. 5. Two transformers operating in parallel will share the load depending upon their
 (A) Rating.
(B) Leakage reactance.
(C) Efficiency.
(D) Per-unit impedance.
Answer:  (A) Rating.

Question No. 6.. In large generators protection provided against external faults is

(A) biased differential protection
(B) sensitive earth fault protection
(C) inter-turn fault protection
(D) all of the above.

Answer: (D) all of the above.

Question No. 7. Volt box is a component to
(a) extend voltage range
(6) measure voltage
(c) compare voltage in a box
(d) none of the above
Answer: a

Question No. 8. A single phase Hysteresis motor
 (A) can run at synchronous speed only
 (B) can run at sub synchronous speed only
 (C) can run at synchronous and super synchronous speed
 (D) can run at synchronous and sub synchronous speed

 Answer:  (A) can run at synchronous speed only


Question No. 9. Which type of protection is provided on a generator to protect against stator insulation failure ?

(A) Differential protection
(B) Thermocouple actuated alarm
(C) Over current relay
(D) Reverse power relay.

Answer: (A) Differential protection

Question No. 10. It is required to measure the true open circuit e.m.f. of a battery. The best device is
(a) D.C. voltmeter
(b) Ammeter and a known resistance
(c) D.C. potentiometer
(d) None of the above
Answer: (c) D.C. potentiometer

No comments:

Post a Comment