When flux density is constant in a transformer, hysteresis loss varies as f² V V² f TRUE ANSWER : ? YOUR ANSWER : ?
In DC generators brushes are used for reduce eddy current loss convert ac armature current in to dc collecting of current without any sparkings collecting of voltage TRUE ANSWER : ? YOUR ANSWER : ?
A 3 - Φ slip ring motor has short-circuited rotor. double cage rotor. wound rotor. any of the above. TRUE ANSWER : ? YOUR ANSWER : ?
Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are identical as 4% from no load to full load. Consider the governors operating at 50Hz on no load. What is the operating frequency, if the load is 600 MW? 45 HZ 50 Hz 48 Hz 48.5 Hz TRUE ANSWER : ? YOUR ANSWER : ?
In DC machines shape of net flux density is? peaky in nature sine wave flat tapped or trapezoidal saddle shape TRUE ANSWER : ? YOUR ANSWER : ?
Armature reaction depends on which of the following? both 1 and 2 None of these power factor of load magnitude of load current TRUE ANSWER : ? YOUR ANSWER : ?
In a stepper motor the detente torque means maximum of the static torque with the phase winding excited. maximum of the static torque with the phase winding unexcited. minimum of the static torque with the phase winding excited. minimum of the static torque with the phase winding unexcited. TRUE ANSWER : ? YOUR ANSWER : ?
The emf induced in the dc generator armature winding is DC AC None of these AC and DC TRUE ANSWER : ? YOUR ANSWER : ?
A generator may loose residual magnetism due to heating. any of these. vibrations. over excitation. TRUE ANSWER : ? YOUR ANSWER : ?
Field divertor method of speed control of a DC series motor gives speed above rated one due to reduction of Line current. None of above. Armature current. Field current. TRUE ANSWER : ? YOUR ANSWER : ?