Measurement and Instrumentation 1 EE AND ECE SHORT NOTES

1

Relative permittivity can be measured by ____ bridge Schering [other wrong options are – Wheatstone, Hay’s, De santy, ]

2

Rosette gauges are used to measure strain in more than one direction
[other wrong options are – amplify strain values, measure variable strain, compensate for temperature variations, ]

3

For thermocouple measuring instruments which of the following statements is incorrect ?
If calibrated on D.C., they cannot be used for A.C. signals
[other wrong options are – Their calibration does not change with time or temperature, They read r.m.s. values, They are incapable of standing any overloads, ]

4

Radio frequency can be measured by which of the following frequency meters ?
Hetrodyne frequency meter
[other wrong options are – Weston frequency meter, Electrical resonant frequency meter, None of the above, ]

5

By a ‘Rotameter’ we can measure
flow

[other wrong options are – specific gravity, viscosity, rotation, ]

6

Null type recorders are
potentiometric recorder
[other wrong options are – bridge recorders, LVDT recorders, any of the above, ]

7

An induction watt meter measures
only the true power
[other wrong options are – the reactive power, the apparent power, the true power and the reactive power, ]

8

A very accurate voltmeter, when used to measure voltage across a low resistance, gives inaccurate reading because
the sensitivity of the meter is too low
[other wrong options are – the current drawn by the meter is too low, the higher scale has been selected, any of the above, none of the above]

9

Weston cell is a
good standard of voltage
[other wrong options are – good source of current, good source of power, none of the above, ]

10

Meter ranges are so selected that the indications are obtained near the
middle of the scale
[other wrong options are – top of the scale, bottom of the scale, alone of the above, ]

11

Torque weight ratio will be least in ____ instruments.
dynamo-meter
[other wrong options are – moving iron, moving coil, all above, ]

12

A power factor meter has _____ control springs.
no
[other wrong options are – one, two, four, ]

13

Permanent magnets used in instruments are generally made of
Alnico
[other wrong options are – stainless steel, Y-alloy, cast iron, ]

14

A portable instrument is likely to have ____ clamping.
eddy current

[other wrong options are- gravitational, pneumatic, fluid friction, ]

15

In the measurement of power by two watt-meter method, when the readings of the two watt-meters are equal and opposite, it
can be concluded that power factor is
zero
[other wrong options are – unity, lagging, leading, ]

16

____ type instrument has identical calibration for A.C. as well as D.C. values ?
Hot wire
[other wrong options are – Moving coil, Induction, Moving iron, ]

17

Which of the following instruments cannot be used for the measurement of A.C. as well as D.C. quantities ?
Induction type instruments
[other wrong options are – Electrostatic instruments, Moving iron
instruments, Hot wire instruments, ]

18

Two holes in the disc of energy-meter are drilled at the opposite sides of the spindle to
eliminate creeping at no load
[other wrong options are – improve its ventilation, increase its deflecting torque, increase its braking torque, ]

19

Instrument transformers are
both (a) and (b)
[other wrong options are – potential transformers, current transformers, power transformers, ]

20

If an instrument has cramped scale for larger values, then it follows
logarithmic law
[other wrong options are – square law, uniform law, none of the above, ]