GATE 2022 : National Champion Quiz 4

With respect to power transformer, the distribution transformer of the same rating has

For a balanced A.C bridge

Z₁ = 600∠–140°

Z₂ = 200∠0°

Z₃ = 300∠–90°

Find the value of Z₄.

If a_(auto) is the ratio of high voltage to low voltage of an autotransformer, then the ratio of inductance power transfer to total power transfer is given by:

For the Lissajous pattern shown below, which of the following statement is correct regarding the pattern for x and y signals

A 0-50 mA PMMC instruments is used to measure a current of 25 A . Calculate the value of multiplication factor ‘m’ and resistance to be placed in parallel with instruments. Assume the moving coil resistance as 25 Ω.

A current transformer has no load current 1.62 A and magnetising current 1.4 A. The secondary equivalent impedance is (0.7 + j 0.5) Ω. Find the difference between the actual ratio and nominal ratio of current transformer if the secondary current is found to be 1.98 A.

When the circuit power factor is low. The wattmeter coil connections should be ?

A 230V, 50 Hz, 4-pole, single-phase induction motor is rotating clockwise (forward) direction at a speed of 1425 rpm. If the rotor resistance at standstill is 7.8Ω, then the effective rotor resistance in the backward branch of the equivalent circuit will be

The clock frequency of ramp type DVM is set to 50 kHz. If the ramp voltage falls from 10 V to 0 V in 30 msec. The number of pulses allowed by gating circuit is ?

A digit Digital Multimeter has an error specification of 0.5% of reading plus 10 counts. The value of an unknown resistance is 50 Ω on the 200 Ω scale of the meter. Percentage error on measuring the resistance _________.

For resonating capacitance of 12 pF, resonance occurs at 3 MHz, and at resonating capacitance 360 pF, resonance occurs at 1 MHz. ______pF is self-capacitance of the coil.

The rotor of a 4-pole ac generator is wound with a 200 turns coil. If the flux per pole is 5 m Wb and the rotor runs at a speed of 1500 rpm, the rms value of the induced voltage for this ac generator is nearly