211. To the y-input of a CRO a signal defined by 10 sin 100t is applied. To the x-input the signal 10 cos 100t is fed. The gain for both x-channel and y-channel is the same. The screen shows
A. 82 mV
B.(c) 118 mV
C.(b) 100 mV
D. 5V
212. A certain meter has a sensitivity of 50,000 WV. The current required to deflect the meter movement to full-scale will be
A. 5 RA
B. 10 RA
C. 20 RA
D. 50 RA
213. In digit voltmeter, over-ranging implies that
A. next 4 digits are switched on
B. ?2 digit is switched off
C. ?2 digit is switched on
D. an indicator short growing
214. A 1000 ohms / V meter is used to measure a resistance on 150 V scale. The meter resistance is
A. 150K
B. 1K
C. 6.67 ohms
D. 0.001 ohm
215. One single-phase wattmeter operating on 230 Vand 5A for 5 hours makes 1940 revolutions. Meter constant in revolutions is 400. The power factor of the load will be
A.1
B.0.8
C.0.7
D.0.6
216. An unfinished moving iron voltmetter is used to measure the voltage in an a.c. circuit. If a stray d.c. magnetic field having a component along the axis of the meter coil appears, the meter reading would be
A. unaffected
B. decreased
C. increased
D. either decreased or increased depending on the direction of the d.c. field.
217. A resistance is measured by the voltmeteram meter method employing d.c. excitation and a voltmeter of very high resistance connected directly across the unknown resistance. If the voltmeter and ammeter readings are subject to maximum possible errors of ? 2.4% and ? 1.0 % respectively, then the magnitude of maximum possible percentage error in the value of resistance deduced from the measurement is nearly
A.1.40%
B.1.70%
C.2.40%
D.3.40%
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