R4RIN – MCQs, Mock Tests | Electrical measurements Electrical Measurement MCQ Question Set 10

Q meter operator is the principle of _______

1. Series resonance
2. Current resonance
3. Self-inductance
4. Eddy currents

✅ Correct Answer: 1

A circuit tuned to a frequency of 1.5 MHz and having an effective capacitance of 150 pF. In this circuit, the current falls to 70.7 % of its resonant value. The frequency deviates from the resonant frequency by 5 kHz. Q factor is?

1. 50
2. 100
3. 150
4. 200

✅ Correct Answer: 3

A circuit tuned to a frequency of 1.5 MHz and having an effective capacitance of 150 pF. In this circuit, the current falls to 70.7 % of its resonant value. The deviates from the resonant frequency are 5 kHz. Effective resistance of the circuit is?

1. 2 Ω
2. 3 Ω
3. 5.5 Ω
4. 4.7 Ω

✅ Correct Answer: 4

Q Meter is used to measure ____

1. Q factor of an inductive coil
2. Only the effective resistance
3. Only bandwidth
4. Q factor of an inductive coil, the effective resistance, and bandwidth

✅ Correct Answer: 4

CRO stands for _____

1. Cathode Ray Oscilloscope
2. Current Resistance Oscillator
3. Central Resistance Oscillator
4. Capacitance Resistance Oscilloscope

✅ Correct Answer: 1

C.R.O gives _______

1. actual representation
2. visual representation
3. approximate representation
4. incorrect representation

✅ Correct Answer: 2

Oscilloscope is _______

1. a ohmmeter
2. an ammeter
3. a voltmeter
4. a multimeter

✅ Correct Answer: 3

Electron beam is deflected in _______

1. 1 direction
2. 4 directions
3. 3 directions
4. 2 directions

✅ Correct Answer: 4

CRO is a ______

1. fast x-y plotter
2. slow x-y plotter
3. medium x-y plotter
4. not a plotter

✅ Correct Answer: 1

CRO can’t display microseconds time.

1. True
2. False
3. all of the above
4. None of the mentioned

✅ Correct Answer: 2

Typically oscilloscope represents ______

1. current and time
2. resistance and time
3. voltage and time
4. power and time

✅ Correct Answer: 3

Electron gun section _____

1. provides sharp beam
2. provides poorly focussed beam
3. doesn’t provide any beam
4. provides electrons only

✅ Correct Answer: 1

Control grid is given _______

1. positive voltage
2. negative voltage
3. negative voltage
4. zero voltage

✅ Correct Answer: 2

What determines light intensity in a CRT?

1. voltage
2. current
3. momentum of electrons
4. fluorescent screen

✅ Correct Answer: 3

Effect of negative voltage to the grid is ______

1. no force
2. a gravitational force
3. an attractive force
4. a repulsive force

✅ Correct Answer: 4

Electron beam diverges.

1. True
2. False
3. all of the above
4. None of the mentioned

✅ Correct Answer: 1

Focusing and accelerating anodes are ____

1. rectangular
2. cylindrical
3. spherical
4. square

✅ Correct Answer: 2

Deflection system of a CRT consists of _____

1. 4 plates
2. 6 plates
3. 2 plates
4. 8 plates

✅ Correct Answer: 3

Horizontal deflection is given by ____

1. x = Kx
2. x = Vx
3. x = 1
4. x = Kx Vx

✅ Correct Answer: 4

Vertical deflection is given by ________

1. y = Ky Vy
2. y = Ky
3. x = 1
4. y = Vy

✅ Correct Answer: 1

What provides a periodic voltage waveform?

1. sweep generator
2. voltmeter
3. oscillator
4. amplifier

✅ Correct Answer: 1

Visible spot must be moved in _______

1. two directions
2. one direction
3. three directions
4. four directions

✅ Correct Answer: 2

Spot is displayed only when _______

1. frequencies are different
2. frequencies are zero
3. frequencies are same
4. voltage is high

✅ Correct Answer: 3

What is done to make the trace horizontal?

1. negative voltage is applied
2. positive voltage is applied
3. no voltage is applied
4. voltage is synchronised

✅ Correct Answer: 4

A single cycle appears on the screen when _______

1. sweep and signal frequencies are equal
2. sweep and signal frequencies are not equal
3. sweep and signal frequencies are zero
4. sweep frequency is greater than signal frequency

✅ Correct Answer: 1

What is the flyback period?

1. voltage is very high
2. current is very low
3. voltage is zero
4. current is very high

✅ Correct Answer: 3

Sinusoidal voltage is not observed on the screen.

1. True
2. False
3. all of the above
4. None of the mentioned

✅ Correct Answer: 2

During trace time, voltage is decreasing with time.

1. True
2. False
3. all of the above
4. None of the mentioned

✅ Correct Answer: 2

Light produced in a screen is ____

1. disappears immediately
2. does not disappear at all
3. is not visible to the eye
4. disappears slowly

✅ Correct Answer: 4

What is the role of CRT?

1. to emit electrons
2. to emit protons
3. to emit neutrons
4. to emit alpha particles

✅ Correct Answer: 1

Input signals are amplified using _______

1. rectifier
2. amplifier
3. oscillator
4. op amp

✅ Correct Answer: 2

Amplifier stage is ______

1. half band
2. full band
3. wide band
4. narrow band

✅ Correct Answer: 3

Role of an attenuator is ________

1. to boost the signal
2. to distort the signal
3. to remove noise
4. to improve the operation

✅ Correct Answer: 4

Amplifier is multiple stage in a CRO.

1. True
2. False
3. all of the above
4. None of the mentioned

✅ Correct Answer: 1

Input stage in the amplifier consists of _____

1. oscillator
2. attenuator
3. rectifier
4. op amp

✅ Correct Answer: 2

Phase inverter is used in an amplifier in the CRO because ____

1. phase inversion is needed
2. no phase inversion is needed
3. it is needed to operate a push pull
4. it provides voltage stability

✅ Correct Answer: 3

BJT is used in the amplifier stage.

1. True
2. False
3. all of the above
4. None of the mentioned

✅ Correct Answer: 1

Why is a delay line used in a CRO?

1. to boost the signal
2. to distort the signal
3. to provide signal delay
4. for stability

✅ Correct Answer: 3

CRO uses ______

1. 2 delay lines
2. 3 delay lines
3. 4 delay lines
4. 5 delay lines

✅ Correct Answer: 1

T section in a delay circuit of CRO acts as ____

1. high pass filter
2. low pass filter
3. band pass filter
4. band reject filter

✅ Correct Answer: 2

Lumped parameter delay line consists of______

1. RC networks
2. RL networks
3. LC networks
4. Resistive networks

✅ Correct Answer: 3

Delay for the T section is given by ____

1. ts = 1⁄fc
2. ts = 1
3. ts = 1⁄π
4. ts = 1⁄πfc

✅ Correct Answer: 4

Distributed parameter delay line is a transmission line.

1. True
2. False
3. all of the above
4. None of the mentioned

✅ Correct Answer: 2

Inductance does not affect a transmission line.

1. True
2. False
3. all of the above
4. None of the mentioned

✅ Correct Answer: 2

Typical values for a distributed parameter delay line are ________

1. Zo = 10 Mῼ and td = 10 nsec/m
2. Zo = 1 kῼ and td = 500 nsec/m
3. Zo = 1000 ῼ and td = 180 nsec/m
4. Zo = 100 Gῼ and td = 275 nsec/m

✅ Correct Answer: 3

What is the effect of the signal delay on the sweep generator?

1. no effect
2. input increases in magnitude
3. output doesn’t get any delay
4. output gets sufficient delay

✅ Correct Answer: 4

Front panel of a CRO has ______

1. 4 sections
2. 8 sections
3. 15 sections
4. 20 sections

✅ Correct Answer: 1

What is the role of the intensity section in a CRO?

1. decreases the light intensity
2. controls light intensity
3. increases the light intensity
4. keeps the light intensity zero

✅ Correct Answer: 2

What is the role of the focus section in a CRO?

1. increases the focus
2. decreases the focus
3. controls sharpness
4. maintains the focus zero

✅ Correct Answer: 3

What is the role of astigmatism in a CRO?

1. increases the intensity
2. used for voltage stability
3. diminishes the intensity
4. focus control

✅ Correct Answer: 4

What is the role of scale illumination in a CRO?

1. measurement
2. illumination
3. sharpness
4. stability

✅ Correct Answer: 1

What is the role of an invert in a CRO?

1. inverts the output
2. inverts the input
3. attenuates the input
4. magnifies the input

✅ Correct Answer: 2

X10 in a CRO means ________

1. one tenth
2. control knob
3. 10 times as normal
4. attenuate the voltage by 10 times

✅ Correct Answer: 3

Position knob in a CRO indicates _____

1. voltage position only
2. time position only
3. current position only
4. any pattern’s position

✅ Correct Answer: 4

Alternate is used to shift the inputs.

1. True
2. False
3. all of the above
4. None of the mentioned

✅ Correct Answer: 1