Medical Instrumentation Mid - II, November - 2014

1.A differential amplifier has a differential gain of 2000 and a common mode gain of 0.2 The CMRR in dB is equal to
  • 10000
  • 400
  • 80
  • 40
Answer: C
2.A basic _____ amplifier is formed by three op-amps and seven resistors.
  • Differential
  • Instrumentation
  • Isolation
  • Carrier
Answer: B
3.The main difference between the isolation amplifier and instrumentation amplifier is
  • An instrumentation amplifier has an input stage
  • An instrumentation amplifier has an output stage
  • The input, output, and power supply stages of an isolation amplifier are all electrically isolated from each other
  • An instrumentation amplifier has a differential stage
Answer: C
4.The noise pick-up from electromagnetic coupling is reduced by
  • Shielding
  • Twisting the circuit conductors
  • Grounding
  • All of the above
Answer: D
5.Potentiometric recorders usually provide a frequency response of _________ at 25cm peak-to peak or at less amplitude
  • 1 Hz-6Hz
  • 10Hz-60Hz
  • 100Hz- 1000Hz
  • 20Hz-2000Hz
Answer: A
6.The thermal writing occurs when specially treated thermal sensitive paper is heated to
  • 500C-800C
  • 900C-1100C
  • 1100C-1400C
  • 1500C-1800C
Answer: B
7.________________ Recorders can be conveniently used to record a number of slowly varying physiological signals.
  • Ink jet
  • Ultra-violet
  • Potentiometric
  • Electrostatic
Answer: C
8.__________ is defined as the maximal current at which the subject can withdraw voluntarily.
  • Threshold of perception
  • Let-go current
  • Leakage currents
  • Macro shocks
Answer: B
9.Grounding creates ___________resistance path to earth.
  • A low
  • A high
  • Absolutely Zero
  • Infinite
Answer: A
10.The currents that cause ventricular fibrillation are termed as__________
  • Macro shocks
  • Micro shocks
  • Let-go currents
  • Gross shocks
Answer: B
11.The common mode rejection (CMR) is the CMRR expressed in__________
Answer: Decibels(dB)
12.A good differential amplifier has a _________ CMRR
Answer: high
13._____________ is high frequency analog recorder which employs a high resolution device to produce records on low cost paper at speeds of 250mm/s
Answer: Electrostatic Recorder
14.__________________ is defined as the shortest duration pulse which can be represented at true value by the recorder.
Answer: Peak Capture
15.For physiological effect of electricity to occur ____________ must become a part of electric circuit.
Answer: Human body
16.To obtain zero frequency response of the dc amplifier and inherent stability of capacitance coupled amplifier a___________ amplifier is used.
Answer: Carrier
17.Ultra violet recorders make use of special _____________ paper which requires careful storing.
Answer: UV sensitive Paper
18.Current at the ________________ is the minimal current that an individual can detect.
Answer: Threshold of perception
19.At current levels just higher than let-go currents can cause_______________
Answer: Physical injury or burns
20.The major source of potentially lethal currents in any instrument is __________________
Answer: Leakage currents