Electrical Measurement

Quiz

 

1. The Input Impedance of CRO is nearly
   1.   around one mega ohm
   2.   around 100 ohms
   3.   around 10 ohms
   4.   zero
2. How many time base circuits does a dual trace CRO have?
   1.   1
   2.   2
   3.   3
   4.   4
3. Holes are filled on the opposite side of the disc of an induction type energy meter to
   1.   increse the deflecting torque
   2.   balance the disc
   3.   avoid creep on no load
   4.   dissipate heat energy due to eddy currents
4. The Principle of operation of an LVDT is based on variation of
   1.   reluctance
   2.   permeance
   3.   self inductance
   4.   mutual inductance
5. The Wheatstone bridge method of resistance measurement is ideally suitable for the measurement of resistance values in the range of
   1.   100kΩ to 10MΩ
   2.   100Ω to 10kΩ
   3.   0.1Ω to 100Ω
   4.   0.001Ω to 1Ω
6. In a two-wattmeter method of measuring power one of the wattmeters is reading zero watts. The power factor of the circuit is
   1.   zero
   2.   0.5
   3.   0.8
   4.   1
7. Which meter has highest accuracy
   1.   Electrodynamometer
   2.   Moving Iron
   3.   PMMC
   4.   Rectifier
8. The circuit genearally used in digital instruments to convert sine waves into rectangular pulses is a
   1.   sample and hold circuit
   2.   sawtooth generator
   3.   Schmitt trigger
   4.   differential amplifier
9. In a LVDT, the two secondary voltages
   1.   are independent on the core position
   2.   vary equally depending on the core position
   3.   vary unequally depending on the core position
   4.   vary equally depending on the core position
10. No eddy current and hysteresis losses occur in
    1.   Electrodynamometer instruments
    2.   PMMC type instruments
    3.   Electrostatic instruments
    4.   Moving-iron instruments