Electrical Machines
A 220 V dc machine has an armature resistance of 1Ω.If the full-load current is 20 A, the differenc in the induced voltages when the machine is running as a motor and as a generator is

 zero
 20 V
 40 V
 50 V

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
In case of a DC Shunt motor if the load is decreased to some extent, what will happen to its speed?

 The speed will increase in proportion to reduction in load.
 The speed will increase abruptly.
 The speed will increase gradually.
 The speed will remains almost constant.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
In a DC machine

 current and emf in armature are alternating.
 emf in armature conductors and at the terminals is alternating.
 current and emf in armature are unidirectional
 current and emf at the terminals are alternating.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
Cogging and crawling are phenomena associated with

 any of the above.
 the former at a fraction of its rate speed and the latter during starting.
 cage induction machines and they are essentially the same.
 the former during starting and the latter at a fraction of its rated speed.

ANSWER DOWNLOAD EXAMIANS APP