How much energy does the kettle transfer?

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The discussion centers on calculating the energy transferred by an electric kettle labeled "230V, 2.3kW" that takes 2.5 minutes to boil water. The key formula for energy transfer is derived from power, where energy (E) equals power (P) multiplied by time (t). Participants clarify that the charge of the electron and voltage are not necessary for this calculation. Understanding that power represents the rate of energy transfer simplifies the problem significantly. The conversation highlights the learning process in physics and the realization of how concepts interconnect.
Christopher
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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 energy to?
Please help

Chris
 
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ps: the italic -19 is meant to be a small -19 above to the right of the 10.
 
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 :biggrin:
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! :smile:
 
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Christopher said:
... but now it makes so much sense I feel quite stupid...lol! :smile:

That's what Physics is all about!
 

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