Electrical Machines In a synchronous machine, if φ is the flux per pole and f is the frequency of the emf induced E then E ∝ φf E ∝ 1/(φf) E ∝ f/φ E ∝ φ/f E ∝ φf E ∝ 1/(φf) E ∝ f/φ E ∝ φ/f ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes 1/4 of the intial value 1/2 of the initial value twice the initial value 4 time the initial value 1/4 of the intial value 1/2 of the initial value twice the initial value 4 time the initial value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor when the length of the air gap is increased, the magnetizing current of the motor increases while the short circuit current __________________. kept constant to certain value. remains unchanged. decreased. increased. kept constant to certain value. remains unchanged. decreased. increased. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Dummy coils are used for mechanical balancing. All of these increasing efficiency. reducing armature reaction. mechanical balancing. All of these increasing efficiency. reducing armature reaction. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a seperately excited DC Motor if field current is increased, it will Increase speed Reduce armature heating. Increase acceleration duration. Reduce starting torque. Increase speed Reduce armature heating. Increase acceleration duration. Reduce starting torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Induction motor operation depends on stationary magnetic field. rotating magnetic field. either of these. None of these stationary magnetic field. rotating magnetic field. either of these. None of these ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS