A 2 kW electric fire is switched on for 30 minutes. How many Units of electricity does it use?

Units of electricity are measured in kWh (kilowatt-hours).
We have our power in kW (2 kW)
We have our time in minutes (30 minutes)
Looking at the units, we can see that:
kW x minutes = kWminutes (kWm)
and
kW x hours = kWhours    (kWh)
 
So, to get our answer in kWh, we must first convert our time to hours:
30 minutes = 0.5 hours
 
then
2 kW x 0.5 hours = 1 kWh
 
So our answer is 1 kWh.

AW
Answered by Andrew W. Physics tutor

18580 Views

See similar Physics GCSE tutors

Related Physics GCSE answers

All answers ▸

what is ohm's law?


A 15kg cannonball and a 1kg football are dropped to the ground from a height of 10 metres. Calculate the speed of the cannonball and of the football just before they hit the ground (you may ignore air resistance).


Why do objects reach terminal velocity?


What is cosmic microwave background, and where does it come from?


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences