Temperature and Internal Energy/Time to heat water

juanita
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A cup of water is scooped up from a swimming pool of water. Compare the temperature T and the internal energy U of the water, in both the cup and the swimming pool.
a) Tpool is less than Tcup, and the U is the same.
b) Tpool is equal to Tcup, and Upool is less than Ucup.
c) Tpool is equal to Tcup, and Upool is greater than Ucup.
d) Tpool is greater than Tcup, and the U is the same.

A 5 kW heater is used to heat water. How long will it take to heat 20 kg of water from 20 degrees celsius to 100 degrees celsius?
a) 32 minutes
b) 2 minutes
c) 12 minutes
d) 22 minutes

any help would be appreciated, thanks!
 
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What are your thoughts on how to solve the problems? What equations (from your textbook or class lecture) do you think would apply here?
 

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