PYQs Based test 16: Electrical & Electronic Measurements

Power consumed by a balanced 3 – phase, 3 – wire load is measured by the two wattmeter method. The first wattmeter reads twice that of the second, then the load impedance angle in radians is –

A (0-50)A moving coil ammeter has a voltage drop of 0.1V across its terminals at full scale deflection. The external shunt resistance (in milliohms) needed to extend its range to (0 - 500 A) is –

A 10 ½ digit timer counter possesses a base clock of frequency 100 MHz. When measuring a particular input, the reading obtained is the same in: (i) Frequency mode of operation with a gating time of one second and (ii) Period mode of operation (in the × 10 ns scale). The frequency of the unknown input (reading obtained) in Hz is _____________.

A stationary closed Lissajous pattern on an oscilloscope has 3 horizontal tangencies and 2 vertical tangencies for a horizontal input with frequency 3 kHz. The frequency of the vertical input is

A dc voltage with ripple is given by V(t) = [100 + 10 sin (ωt) - 5 sin (3ωt)] volts. Measurements of this voltage v(t), made by moving-coil and moving-iron voltmeters, show, readings of V₁ and V₂ respectively. The value of V₂ - V₁, in volts, is _________.