A cup of boiling water (100 degrees C) (0.2kg) transfers 20 000J of heat to its surrounding in 1 hour. What temperature is the water in the kettle after 1 hour?
To answer this we need to use the equation Q = MC(T1-T2)
We want to know what T2 is (ie the temperature after one hour).
So rearrange the equation to get T2 = T1 - Q/MC
No substitute the values given: T2 = 100 - 20000/(0.2 x 4200) = 76.2 0C
CJ
Related Physics GCSE answers
All answers ▸Why does your hair stand on end when you touch a Van de Graaff generator?
What is the reaction force? (eg from the ground or table)
A car accelerates in 12s from 10m/s to 50m/s. Calculate its acceleration.
Compare the medical uses of ultrasound and X-rays. Your answer should include the risks, if any, and precautions, if any, associated with the use of ultrasound and X-rays. [6 marks]