ECE :: Measurements and Instrumentation
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Insertion of a dielectric material between the plates of an air capacitor
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Two ammeters A and B are connected in parallel in a circuit carrying 100 A. Their resistances are 0.8 mΩ. Their readings will be.
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In figure, Za = 100∠50°, Zb = 300∠-90° and Zc = 200∠0°. For balanced condition, Zd will be
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In household energy meters the flux of series magnet is in phase with current but the flux of shunt magnet lags the voltage by 88°. The reading of energy meters
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Assertion (A): A universal RLC bridge has a battery and also a high frequency ac source.
Reason (R): RLC bridge uses a Wienbridge arrangement for measuring capacitance.
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The power factor of a single phase load can be calculated if instruments available are
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A variable reluctance type tachometer has 150 teeth on rotor. The counter records 13500 pulse/sec. The rotational speed is
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The current through the coil of an electromagnet is doubled. The magnetic field around the coil
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In a moving iron voltmeter the coil has a resistance of 20 Ω and an inductance of 0.3 H. The swamping resistance in 2000 Ω. To ensure correct reading with dc as well as 50 Hz ac, the value of capacitor to be connected in parallel with swamping resistance should be