# How much energy does the kettle transfer?

I know that Tom wants us to at least have one go at answering the question ourselves but Ihave been haunted by this question for almost a week now and I don't feel ay closer to answering it.

I have been given the electron charge which is 1.6*10-19 C and I have been given the question "An electric kettle is labelled "230V, 2.3kW". It takes 2.5 minutes to boil some water.
How much energy does the kettle transfer?

How am I meant to answer this questin if I am not given some sort of other energy to compare the electric enegy to?

Chris

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ps: the italic -19 is meant to be a small -19 above to the right of the 10.

Chi Meson
Homework Helper
You have been given voltage and power. Power is the rate of energy transfer(P = E/t) . So "watts" = "joules"/"seconds" therefore, E = Pt "joules" = "watts" x "seconds" . You don't need the charge of the electron nor the voltage for this problem.

Thankyou
It never seemd to occur to me that power is the energy transfer but now it makes so much sense I feel quite stupid...lol! :rofl:

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Chi Meson