218. The number of comparators needed in a parallel conversion type 8-bit A to D Convertor is
A.8
B.16
C.255
D.256

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219. In d.c. potentiometer measurements, a second reading is often taken after reversing the polarities of the d.c. supply and the unknown voltage and the aver-a of the two reading is taken. This is with a view of eliminate the effects of
A. ripples in the d.c. supply
B. stray magnetic fields.
C. stray thermal emfs
D. erroneous standardisation

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220. A digital voltmeter measures
A. peak value
B. peak-to-peak value
C. rms value
D. average value

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221. Which of the following instruments will have the same calibration on both a.c. And d.c.?
A. Electrodynamometer type
B. Moving iron type
C. Moving coil type
D. Induction type

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222. The deflection of hot wire instrument depends on
A. RMS value of alternating current
B. voltage
C. average value of a.c. current
D. Instantaneous value of a.c. current

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223. Megger is an instrument for
A. measuring current
B. measuring voltage
C. testing insulation
D. measuring power

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224. The instrument whose deflection is given dM by the expression 0 is known is
A. electrodynamic type
B. repulsion type
C. electrostatic type
D. attraction type

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