Compensating winding is located on which potion of DC Machines: Commutating poles Outside yoke Pole shoes None of these Correct answer: 3. Pole shoes Compensating winding is located on the pole shoes of DC machines.
Electric Current is measured in: volts amps ohms watts Correct answer: 2. Amps The SI unit of electric current is amps. Electric current is measured in amps
A DC Generator beyond critical field resistance will generate: Maximum possible current Maximum possible voltage No Voltage Half voltage Correct answer: 3. No voltage Explanation: A DC Generator beyond critical field resistance will generate no voltage.
A 120/1600 V transformer takes no-load current of 5 A at a lagging power factor of 0.3 The core losses are: 90 W 180 W 360 W 720 W Correct answer: 2. 180 W Explanation: Core losses formula = V1 I0 Cos φ = 120 * 5 * 0.3 = 180 W
Teeth in armature of DC Machines are skewed to reduce: Vibrations Eddy current losses Hysteresis losses None of these Correct answer: 1.Vibrations Teeth in the armature of DC Machines are skewed to reduce vibrations in the machine.
The Armature of DC Machines is laminated to: Reduce the mass of machine Reduce inductance in machine To reduce the eddy current losses Fight against hysteresis losses Correct answer: 3. To reduce the eddy current losses The Armature of DC Machines is laminated to reduce the eddy current losses in Machine.
The windage loss in DC motor is proportional to: Cube root of supply voltage Square of supply voltage Square of armature speed Cube root of flux density Correct answer: 3. Square of armature speed Explanation: The windage losses in DC Motor are proportional to the square of armature speed.
Voltage is measured in: Amps Volts Ohms Watts Correct answer: 2. Volts Explanation: Voltage is measured in volts. The SI unit of voltage is volts and volts is the unit in which we measure the voltage.
Grading of cables is done in order to: Achieve uniform electrostatic stress Reduce the size of cable Reduce insulation being used All of these Correct answer: 4. All of these Grading of cables is defined as the process of achieving uniform electrostatic stress in the dielectric of cables. In a single-core cable the electrostatic stress … Read more
The primary and secondary windings are wrapped on each other to reduce: Copper losses Iron losses Resistance of windings Leakage reactance Correct answer: 4. Leakage reactance Explanation: In a practical transformer, the primary and secondary windings are wrapped one on top of the other in such a way that the low-voltage winding innermost, while high … Read more