If a student uses an electric kettle connected to a 230V mains power supply, with a heating power of 1.8kW. Assuming negligable losses, answer the following: a) find the current in the kettle b) find the total energy transferred in 2 minutes of operation
a) The governing equation here is Power = current x voltage or P=IV. using this formula, 1,800 = I x 230 => I=1800/230 = 7.83 A (3sf) b) as watts is equal to joules/seconds, we can find the energy in joules by multiplying the power by the time of operation in seconds, this would be 120 seconds for 2 minutes. Therefore the total energy used is 1,800*120 = 216,000J
CP
Related Physics GCSE answers
All answers ▸State one advantage and one disadvantage of using a CT scanner, compared with ultrasound scanning, for forming images of the inside of the human body. (2 Marks)
A rocket travels at 500m/s two minutes after its take-off. If it was initially stationary, calculate its acceleration. If the rocket has a mass of 1800kg, what force is required to give it an acceleration of 2m/s^2?
Describe one method by which the distance to stars from Earth is measured, and one modern improvement to this method which increases its accuracy.
What are the definitions of a)voltage and b)current?