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 discharge of a capacitor through a ballistic galvanometer produces a damped frequency of 0.125 Hz and successive swings of 120, 96 and 76.8 mm. The logarithmic decrement is?

A. 0.225
B. 0.565
C. 0.484
D. 0.7887
Answer» B. 0.565
Discussion
2.

The discharge of a capacitor through a ballistic galvanometer produces a damped frequency of 0.125 Hz and successive swings of 120, 96 and 76.8 mm. The damping ratio is?

A. 0.0568
B. 0.0887
C. 0.0357
D. 0.0441
Answer» D. 0.0441
Discussion
3.

A PMMC rated as 100 A is used in a rectifier type of instrument which uses full wave rectification. What is the sensitivity on sinusoidal AC?

A. 4.5 k /V
B. 18 k /V
C. 10 k /V
D. 9 k /V
Answer» E.
Discussion
4.

Two 100 A full-scale PMMC meters are employed to construct a 10 V and a 100 V full-scale voltmeter. These meters will have figure of merit (sensitivities) as?

A. 10 k /V and 10 k /V
B. 100 k /V and 10 k /V
C. 10 k /V and 100 k /V
D. 10 k /V and 1 k /V
Answer» B. 100 k /V and 10 k /V
Discussion
5.

A moving coil of a meter has 250 turns and a length and depth of 40 mm and 30 mm respectively. It is positioned in a uniform radial flux density of 450 mT. The coil carries a current of 160 mA. The torque on the coil is?

A. 0.0216 N-m
B. 0.0456 N-m
C. 0.1448 N-m
D. 1 N-m
Answer» B. 0.0456 N-m
Discussion
6.

A moving iron ammeter produces a full-scale torque of 240 N-m with a deflection of 120 at a current of 10 A. the rate of change of self-inductance ( H/rad) of the instrument at full scale is?

A. 2.0 H/rad
B. 4.8 H/rad
C. 12.0 H/rad
D. 114.6 H/rad
Answer» C. 12.0 H/rad
Discussion
7.

A 50 Hz voltage is measured with a moving iron voltmeter and a rectifier type AC voltmeter connected in parallel. If the meter readings are Va and Vb respectively. Then the form factor may be estimated as?

A. ( frac{V_a}{V_b} )
B. ( frac{1.11 V_a}{V_b} )
C. ( frac{ sqrt{2} V_a}{V_b} )
D. ( frac{ V_a}{V_b} )
Answer» C. ( frac{ sqrt{2} V_a}{V_b} )
Discussion
8.

A current of [2 + ( sqrt{2} ) sin (314t + 30) + 2 ( sqrt{2} ) cos (952t +45)] is measured with a thermocouple type, 5A full scale, class 1 meter. The meter reading would lie in the range?

A. 5 A 1 %
B. (2 + 3 ( sqrt{2} )) A 1%
C. 3 A 1.7 %
D. 2 A 2.5 %
Answer» D. 2 A 2.5 %
Discussion
9.

A rectifier type AC voltmeter consists of a series resistance R, an ideal full-wave rectifier bridge and a PMMC instrument. The internal resistance of the instrument is 100 and a full- scale deflection is produced by a DC current of 1 mA. A voltage of 100 V (rms) is applied to the input terminals. The value of R required is?

A. 63.56
B. 89.83
C. 89.83 k
D. 141.3 k
Answer» D. 141.3 k
Discussion
10.

A current of 8 + 6 ( sqrt{2} ) (sin ( t + 30 )) A is passed through three meters. The respective readings (in ampere) will be?

A. 8, 6 and 10
B. 8, 6 and 8
C. 8, 10 and 10
D. -8, 2 and 2
Answer» D. -8, 2 and 2
Discussion