Electrical Machines
For a given torque, reducing diverter resistance of a DC series motor causes

 decrease in speed but armature current remains the same.
 increase in speed but armature currnet remains the same.
 decrease in speed demanding less armature current.
 increase in speed demanding more armature current.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
If the frequency of input voltage of a transformer is increased keeping the magnitude of voltage unchanged, then

 both hysteresis loss(Ph) and eddy current loss(Pe) will increase
 Pe will increase but Ph will decrease
 Ph will decrease but Pe will remain same
 Ph will increase but Pe will decrease

ANSWER DOWNLOAD EXAMIANS APP