Explore topic-wise MCQs in Electrical Measurements.

This section includes 10 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Measurements knowledge and support exam preparation. Choose a topic below to get started.

1.

The simultaneous applications of signals x (t) and y (t) to the horizontal and vertical plates respectively, of an oscilloscope, produce a vertical figure of 8 displays. If P and Q are constants and x(t) = P sin (4t + 30), then y(t) is equal to _________

A. Q sin (4t -30)
B. Q sin (2t +15)
C. Q sin (8t +60)
D. Q sin (4t +30)
Answer» C. Q sin (8t +60)
2.

A slide wire potentiometer has 10 wires of 2 m each. With the help of a standard voltage source of 1.045 V, it is standardized by keeping the jockey at 104.5 cm. If the resistance of potentiometer wires is 2000 , then the value of working current is?

A. 1 mA
B. 10 mA
C. 0.1 mA
D. 0.5 mA
Answer» C. 0.1 mA
3.

A galvanometer with a full-scale current of 10 mA has a resistance of 1000 . The multiplying power of a 100 shunt with this galvanometer is?

A. 110
B. 100
C. 11
D. 10
Answer» D. 10
4.

Resistance is measured by the voltmeter-ammeter method employing DC excitation and a voltmeter is connected directly across the unknown resistance. If the voltmeter and ammeter readings are subject to maximum possible errors of 2.4 % and 1% respectively, then the magnitude of the maximum possible percentage error in the value of resistance deduced from the measurement is?

A. 1.4 %
B. 1.7 %
C. 2.4 %
D. 3.4 %
Answer» E.
5.

A 100 A ammeter has an internal resistance of 100 . The range is to be extended to 500 A. The shunt required is of resistance __________

A. 20.0
B. 22.22
C. 25.0
D. 50.0
Answer» D. 50.0
6.

A DC ammeter has a resistance of 0.1 and its current range is 0-100 A. If the range is to be extended to 0-500 A, the meter requires which of the following shunt resistance?

A. 0.010
B. 0.011
C. 0.025
D. 1.0
Answer» D. 1.0
7.

A DC ammeter is rated for 15 A, 250 V. The meter constant is 14.4 A-s/rev. The meter constant at rated voltage may be expressed as __________

A. 3750 rev/kW-h
B. 3600 rev/kW-h
C. 1000 rev/kW-h
D. 960 rev/kW-h
Answer» D. 960 rev/kW-h
8.

A 35 V DC supply is connected across a resistance in series with an unknown resistance R. a voltmeter having a resistance of 1.2 k is connected across 600 resistance and reads 5 V. The value of the known resistance is 600 . The value of resistance R will be?

A. 120
B. 400
C. 1.8 k
D. 2.4 k
Answer» E.
9.

A setup is used to measure resistance R. The ammeter and voltmeter resistance are 0.01 and 2000 respectively. Their readings are 2 A and 180 V respectively, giving a measured resistance of 90 . The percentage error in the measurement is?

A. 2.25 %
B. 2.35 %
C. 4.5 %
D. 4.71 %
Answer» E.
10.

Ra and Rd are the opposite arms of a Wheatstone bridge as are Rc and Rb. The source voltage is applied across Ra and Rc. Then when the bridge is balanced which one of the following is true?

A. R<sub>a</sub> = R<sub>c</sub> R<sub>d</sub>/R<sub>b</sub>
B. R<sub>a</sub> = R<sub>b</sub> R<sub>c</sub>/R<sub>d</sub>
C. R<sub>a</sub> = R<sub>b</sub> Rd/R<sub>c</sub>
D. R<sub>a</sub> = R<sub>b</sub> + R<sub>c</sub> + R<sub>d</sub>
Answer» C. R<sub>a</sub> = R<sub>b</sub> Rd/R<sub>c</sub>