Measurement and Instrumentation The meter constant of a single phase 240 V induction watthour meter is 400 revolutions per KWh. The speed of the meter disc for a current of 10 Amperes of 0.8 p.f lagging will be 12.8 rpm. 21.1 rpm. 18.2 rpm. 16.02 rpm. 12.8 rpm. 21.1 rpm. 18.2 rpm. 16.02 rpm. ANSWER DOWNLOAD EXAMIANS APP
Measurement and Instrumentation The current ‘I’ through a resistance R is measures with the following uncertainties I = 4 A ± 0.5%, R = 100Ω±0.2%. If power is computed from these two measured quantities, the uncertainty in the power computed will be 1.5% 1% 1.2% 0.5% 1.5% 1% 1.2% 0.5% ANSWER DOWNLOAD EXAMIANS APP
Measurement and Instrumentation Most accurate measurement of unknown resistance will be by Wheatstone bridge Voltmeter and ammeter Potentiometer Ohmmeter Wheatstone bridge Voltmeter and ammeter Potentiometer Ohmmeter ANSWER DOWNLOAD EXAMIANS APP
Measurement and Instrumentation What is the expression for momentum? force × displacement mass × acceleration mass × velocity change of velocity / time force × displacement mass × acceleration mass × velocity change of velocity / time ANSWER DOWNLOAD EXAMIANS APP
Measurement and Instrumentation The current coil of a wattmeter is connected to the CT of R-phase. The potential coil is connected across Y and B phases. The wattmeter measures Active power of Y phase Power proportional to 3 phase power if the load is balanced Reactive power of R phase Active power in R phase Active power of Y phase Power proportional to 3 phase power if the load is balanced Reactive power of R phase Active power in R phase ANSWER DOWNLOAD EXAMIANS APP
Measurement and Instrumentation Commonly used instruments in power system measurement are Electrostatic Moving coil or iron Induction Rectifier Electrostatic Moving coil or iron Induction Rectifier ANSWER DOWNLOAD EXAMIANS APP
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