Multiple choice question for engineering
Set 1
1. All bodies behave as source of _______________
a) Electromagnetic radiation
b) IR radiation
c) Ultra violet radiation
d) None of the mentioned
Answer
Answer: a [Reason:] All bodies behave as a source of electromagnetic radiation under excited state.
2. Which of the following represent spectrum of frequency emission?
a) Absorption spectra
b) Emission spectra
c) EM spectra
d) None of the mentioned
Answer
Answer: b [Reason:] All bodies behave as source of em waves and spectrum of frequency emitted is known as emission frequency.
3. Spectrography doesn’t compute energy of frequency spectrum.
a) True
b) False
Answer
Answer: b [Reason:] Spectrography can be used for calculating energy of frequency spectrum.
4. Which of the following source is used for exciting bodies electrically?
a) DC arc
b) AC arc
c) Spark
d) All of the mentioned
Answer
Answer: d [Reason:] Electrical excitation of body can be carried out using DC arc, AC arc and spark.
5. Which of the following is more used core in spectrometer?
a) Graphite
b) Carbon
c) Aluminium
d) Fullerine
Answer
Answer: a [Reason:] Graphite is more used material than carbon as core in spectrometer.
6. Which of the following represents emission spectra?
a) Continuous spectra
b) Band spectra
c) Line spectra
d) All of the mentioned
Answer
Answer: d [Reason:] Emission spectra is divided into continuous spectra, band spectra and line spectra.
7. Every spectrograph requires dispersion.
a) True
b) False
Answer
Answer: a [Reason:] Spectrograph processes dispersed radiation.
8. Dispersion of radiation is carried out by _____________
a) Prism
b) Grating
c) Both prism and grating
d) Diamond
Answer
Answer: c [Reason:] For dispersing radiation, prism or grating elements are used.
9. IR absorption pattern in absorption spectrography is known as___________
a) Finger print
b) Signature
c) Absorption code
d) Graph
Answer
Answer: a [Reason:] Due to uniqueness IR absorption pattern in absorption spectrography is called fingerprint.
10. Which of the following represents fingerprint region?
a) Less than 7um
b) Between 7um to 15um
c) Greater than 15um
d) Greater than 100um
Answer
Answer: b [Reason:] IR spectrum ranging between 7um to 15um wavelength offer best discrimination between molecules and hence identified as fingerprint region.
Set 2
1. Beam balance is used for _________________
a) Weight comparison
b) Pressure comparison
c) Density comparison
d) None of the mentioned
Answer
Answer: a [Reason:] Beam balance system is used for comparing two difference weights.
2. In electromagnetic balance system, horizontality is detected by ____________
a) Photo electric cell
b) Direct vision
c) Galvanometer
d) Detector circuit
Answer
Answer: a [Reason:] Photo electric cell is used for detecting horizontality in beam balance system.
3. Which of the following application in balance system a PMMC device used for?
a) Restoring balance system
b) Oscillatory action
c) Detection of horizontality
d) None of the mentioned
Answer
Answer: a [Reason:] PMMC device is incorporated for restoring action.
4. Null position is attained when _______________
a) Two weight becomes equal
b) One becomes double of other
c) One becomes zero
d) No null position attained
Answer
Answer: a [Reason:] When two weights becomes equal and bar becomes horizontal it is said to be in null position.
5. In balance system gain of amplifier is _____________
a) Very low
b) Very high
c) Unity
d) Selected according to weight
Answer
Answer: b [Reason:] Very high gain amplifier is used so that moments are balanced.
6. Torque of PMMC device is proportional to _______________
a) Mass
b) Change in two masses
c) Balancing time
d) None of the mentioned
Answer
Answer: b [Reason:] Change in two masses will be proportional to torque produced by PMMC device.
7. Null detection can be accomplished by ______________
a) Photo cell
b) Direct measurement
c) Pneumatic cell
d) All of the mentioned
Answer
Answer: d [Reason:] Null detection can be made by use of photocell, Pneumatic cell and direct measurement.
8. PMMC system always tend to make the system distract from null position.
a) True
b) False
Answer
Answer: b [Reason:] PMMC device are used for beam to restore null position.
9. In a pneumatic balance system, restoring is done by ______________
a) PMMC device
b) Bellows
c) Amplifier
d) Demodulator
Answer
Answer: b [Reason:] Bellow elements are introduced for providing restoring action in pneumatic balance system.
10. In a pneumatic balance system, developed output will be __________
a) Pressure variation
b) Current signal
c) Potential difference
d) None of the mentioned
Answer
Answer: a [Reason:] In pneumatic balance system, develop output signal will be pressure variation.
Set 3
1. SAW stands for ________________
a) Sound actuated wave
b) Surface acoustic wave
c) Sound activated wave
d) Surface activated wave
Answer
Answer: b [Reason:] SAW stands for surface acoustic wave.
2. Quartz can be used as bio sensors.
a) True
b) False
Answer
Answer: a [Reason:] In QCM, piezoelectric nature of quartz is utilized.
3. Direction of acoustic wave in QCM will be ______________
a) Same as crystal surface
b) Opposite to crystal surface
c) Perpendicular to crystal surface
d) None of the mentioned
Answer
Answer: c [Reason:] In QCM, direction of acoustic wave will be perpendicular to crystal surface.
4. Acoustic wave in QCM meets minimum impedance when thickness of device is __________________
a) Equal to wavelength of acoustic wave
b) Product of Half of wavelength of acoustic wave
c) Product of quarter of wavelength of acoustic wave
d) None of the mentioned
Answer
Answer: b [Reason:] When thickness of device is product of half of wavelength of acoustic wave, it meets minimum impedance.
5. Which of the following is most preferred?
a) QCM and SAW sensor
b) QCM and BAW sensor
c) QCM
d) All of the mentioned
Answer
Answer: a [Reason:] Quartz crystal micro balance and surface acoustic wave sensors are used, since it provides impressive sensitivity.
6. Magnetic bio sensor is wide used for____________
a) Blood detection
b) DNA detection
c) ECG detection
d) EMG detection
Answer
Answer: b [Reason:] Magnetic bio sensors are used for DNA detection.
7. QCM stands for _______________
a) Quartz crystal micro balance
b) Quality control balance
c) Quartz crystal magnifier
d) None of the mentioned
Answer
Answer: a [Reason:] QCM stands for Quartz crystal micro balance which uses quartz crystals.
8. Changes in resonant frequency of QCM is proportional to _____________
a) Mass accumulated in crystal
b) Crystal used
c) Time of usage
d) None of the mentioned
Answer
Answer: a [Reason:] Deposition of thin film on crystal surface causes change in resonant frequency of device.
9. BAW stands for __________________
a) Bulk acoustic wave
b) Barrier acoustic wave
c) Barrier avoiding wave
d) Bulk activated wave
Answer
Answer: a [Reason:] BAW stands for Bulk acoustic wave.
10. Non contacting type bio sensors are ____________
a) Radiation type
b) Electromagnetic type
c) Radiation or electromagnetic type
d) None of the mentioned
Answer
Answer: c [Reason:] Bio sensors may be contacting or non contacting type. Non contacting type sensors may be electromagnetic or radiation type.
Set 4
1. Which of the following device is similar to analog comparator?
a) Analog switch
b) MCB
c) Energy meter
d) Digital switch
Answer
Answer: a [Reason:] Analog comparators are similar to analog switch which switches comparing to a predetermined level.
2. Which of the following can act as comparator?
a) Op-amp with negative feedback
b) Op-amp with positive feedback
c) Op-amp without feedback
d) None of the mentioned
Answer
Answer: c [Reason:] Operational amplifier without feedback will act as comparator comparing two input signals.
3. Zero crossing detector has ____________ as reference voltage.
a) +ve Vcc
b) –ve Vcc
c) Zero V
d) 5V
Answer
Answer: c [Reason:] Zero crossing detector compares given signal with zero reference value.
4. Which of the following detect presence of a voltage between two voltages?
a) Zero crossing detector
b) Differential comparator
c) Window comparator
d) None of the mentioned
Answer
Answer: c [Reason:] Window comparators are used to detect presence of a given voltage value between two voltages.
5. Which of the following are used in window comparators?
a) Op-amps and AND gates
b) OP-amps and OR gates
c) Op-amps and XOR gates
d) OP-amps and NAND gates
Answer
Answer: a [Reason:] Circuit of window comparator contains two op-amps and one AND gate.
6. Schmitt trigger is a sine wave generator.
a) True
b) False
Answer
Answer: b [Reason:] Schmitt trigger is a comparator which produces square wave output.
7. Difference between levels on input that causes transition in Schmitt trigger is ___________
a) Hysteresis
b) Threshold
c) Cut-off value
d) Peak value
Answer
Answer: a [Reason:] Hysteresis is the difference between input levels that causes output transition.
8. Threshold voltage for switching in Schmitt trigger is determined by _______________
a) Resistor R1
b) Resistor R2
c) Both resistors
d) None of the mentioned
Answer
Answer: c [Reason:] Threshold voltage for switching is determined by both resistors R1and R2.
9. Which of the following is converted to square wave in Schmitt trigger?
a) Sine wave
b) Triangular wave
c) Pulse wave
d) All of the mentioned
Answer
Answer: d [Reason:] Schmitt trigger converts any wave into square wave.
10. For a particular op-amp hysteresis is governed by _______________
a) Resistor R1
b) Resistor R2
c) Both resistors R1 and R2
d) Op-amp parameters
Answer
Answer: c [Reason:] Hysteresis of a particular op-amp is governed by resistors R1 and R2.
Set 5
1. Piezo electric crystals are low impedance sources.
a) True
b) False
Answer
Answer: b [Reason:] Piezo electric crystals are considered to be high impedance sources.
2. Modulation is used for __________________
a) Reducing loss in transmission
b) Amplification of signal
c) Conversion of signal
d) None of the mentioned
Answer
Answer: a [Reason:] For transmission over long range message signal is mixed with a carrier signal for reducing loss during transmission.
3. In line code transmission, signal is represented by ______________
a) Impulses
b) Train of pulses
c) DC signal
d) Continuously varying signal
Answer
Answer: b [Reason:] In Line code transmission, signal is represented by a train of pulses known as baseband transmission.
4. Which of the following process is explained as detection?
a) Modulation
b) Demodulation
c) Amplification
d) None of the mentioned
Answer
Answer: b [Reason:] Demodulation or retrieving data from signal is known as demodulation or detection.
5. Which of the following is represented as digital transmission?
a) Baseband bit stream transfer
b) Passband bit stream transfer
c) All of the mentioned
d) None of the mentioned
Answer
Answer: c [Reason:] Both baseband and passband signals representing bit streams are considered to be digital transmission.
6. PCM stands for ________________
a) Pulse create message
b) Pulse carry modulation
c) Pulse code modulation
d) None of the mentioned
Answer
Answer: c [Reason:] Pulse code modulation is the process of conversion of analog signals to bit stream.
7. Codec equipment is used for ______________
a) Source coding
b) Source decoding
c) All of the mentioned
d) None of the mentioned
Answer
Answer: c [Reason:] Codec equipments are used for source coding and decoding processes.
8. TCP stands for ___________
a) Tele Call Protocol
b) Transmission Control Protocol
c) Transmission Carry Protocol
d) Transmission Control Parity
Answer
Answer: b [Reason:] TCP stands for transmission control protocol.
9. Tele-transmission is the process of transfer of ______________
a) Analog signals
b) Digital signals
c) Analog and digital signals
d) None of the mentioned
Answer
Answer: c [Reason:] Tele-transmission is the process of both analog and digital transmission.
10. Which of the following is not a digital modulation method?
a) FSK
b) PSK
c) ASK
d) None of the mentioned
Answer
Answer: d [Reason:] Frequency shift keying, phase shift keying and amplitude shift keying are different methods of digital modulation.
