A motor does 4.8kJ of work in 2 minutes. What is its power output?

Power is the RATE of work done or energy transferred.
By the Law of Conservation of Energy, energy cannot be created or destroyed, only converted from one form to another. Power is the rate at which energy is transferred between forms, also known as the rate of work done. To calculate power, we use the following equation:
Power = Energy/Time
where Power is measured in Watts, Energy in Joules and Time in Seconds.
So, for the above question, begin by converting the units and then substitute the values into our equation:
1) 4.8kJ = 4800J
2) 2minutes = 120s
3) P = E/t so P = 4800/120 = 40W

SJ
Answered by Simran J. Physics tutor

10808 Views

See similar Physics GCSE tutors

Related Physics GCSE answers

All answers ▸

Describe the forces acting on an object on earth falling through the air, and how they change from when the object is first released into the air leading to terminal velocity.


A kettle requires 2400 Coulombs of charge to pass through its heating element, with a resistance of 6 Ohms, in a time of 200 seconds in order to boil the water inside it. Calculate the current flowing and the power of the kettle.


As a student rubs his feet along the carpet in his living room, he becomes charged. After this he places his hand on a metal radiator and receives an electric shock. Explain what charge the student obtains, why, and why he receives a shock.


A 70Kg person jumps out of a plane and deploys a parachute, once the parachute is open the wind resistance acting on the person and the parachute is 900N. What is the direction and magnitude of the persons acceleration.


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning