The efficiency of d.c. motor is given by `eta =`

The efficiency of a motor is defined as the ratio of mechanical power output to that with input electric power. The motor is designed to operate at 100 V and it draws a current of 15 A . If output mechanical power of motor is 800 W, then calculate the efficiency of motor .

A 750 W motor drivers a pump which lifts 300 litres of water per minute to a height of 6 meters. The efficiency of the motor is nearly (take acceleration due to gravity to be 10 m//s^(2))

An electric motor operating on a 50 V dc supply draws a current of 12 A . If the efficiency of the motor is 30 % ,estimate the resistance of the windings of the motor.

An electric motor operating on a 50V d.e. supply draws a current of 12A. If the efficiency of the motor is 30\%, estimate the resistance of the windings of the motor.

Thermodynamic efficiency of a cell is given by:

An electric motor operating on 50 volt D.C. supply draws a current of 10 amp. If the efficiency of motor is 40% then the resistance of the winding of the motor is