A single phase motor connected to 415 V, 50 Hz supply takes 30 A at a power factor of 0.7 lagging. Calculate the capacitance required in parallel with the motor to raise the power factor to 0.9 lagging. 76.32 µF 66.32 µF 86.32 µF 96.32 µF TRUE ANSWER : ? YOUR ANSWER : ?
The single line diagram of the simple power system is shown in figure the corresponding reactance diagram is A B D C TRUE ANSWER : ? YOUR ANSWER : ?
A wire pilot is generally economical for distances up to 75 km to 100 km 30 km to 60 km 10 km to 15 km 20 to 25 km TRUE ANSWER : ? YOUR ANSWER : ?
The line currents in amperes in phases a, b and c respectively are 500 +j150, 100 – j600 and – 300 + j600 referred to the same reference vector with phase sequence of abc. Find the symmetrical component of currents. Ia₀ = (100+j50) AIa₁ = (146.41+ j65.47) AIa₂ = (546.41-j165.47) A Ia₀ = (100+j50) AIa₁ = (546.41+j165.47) AIa₂ = (-146.41-j65.47) A Ia₀ = (100+j50) AIa₁ = (200+ j107.75) AIa₂ = (200-j107.75) A Ia₀ = (100+j50) AIa₁ = (546.41+ j165.47) AIa₂ = (546.41-j165.47) A TRUE ANSWER : ? YOUR ANSWER : ?
The relation between electric intensity E, voltage applied V and the distance d between the plates of a parallel plate condenser is E = Vx(d)² E = V/(d)² E = V x d E = V/d TRUE ANSWER : ? YOUR ANSWER : ?
In the RLC series circuit shown in figure, resonance occurs when the value of C is 20 µF. The supply voltages is v(t) = 20 sin (500t) V. Find the value of L. 0.2 H 0.2 mH 5 mH 5 H TRUE ANSWER : ? YOUR ANSWER : ?
In a power network, 400 kV is recorded at a 415 kV bus. A 50 MVAR, 415 kV shunt reactor is connected to the bus. What is the reactive power absorbed by the shunt reactor? 76.45 MVAR 46.45 MVAR 66.45 MVAR 56.45 MVAR TRUE ANSWER : ? YOUR ANSWER : ?
In a single phase energy meter, the shunt electromagnet is energized by a ____of ____ current coil, thick wire of few turns pressure coil, thick wire of few turns pressure coil, thin wire of more turns current coil, thin wire of more turns TRUE ANSWER : ? YOUR ANSWER : ?
A short-shunt dc compound generator supplies 50 A at 300 V. If the shunt field resistance, series field resistance and armature resistance are 30 Ω, 0.03Ω, and 0.05 Ω respectively, determine the e.m.f. generated. 302.5 V 306.5 V 308.5 V 304.5 V TRUE ANSWER : ? YOUR ANSWER : ?