Given that,
Electrical energy of the motor = 2280 J
Kinetic energy = 1606 J
Wasted energy in thermal and sound energy = 550 J
To find,
The efficiency of the motor in percent.
Solution,
Efficiency is defined as the ratio of useful output energy to the total energy.
Total energy = 2280 J
Useful energy = 1606 J
![\eta=(1606)/(2280)* 100\\\\=70.43\%](https://img.qammunity.org/2021/formulas/physics/high-school/rd32xpzyokjymilc5rm7624hci85ctdn0j.png)
So, the efficiency of the motor is 70.43%.