A student seals 200g of ice−cold water in a glass vacuum
(thermos) flask and finds that it warms up by 3.5 K in one hour
SHC of water =2400 Jkg^(−1) K^(−1)
a) Calculate the average rate of heat flow in the flask in watts.
To check this result over a longer period,the student fills the flask with
equal amounts of ice and water all at 0°C, and leaves it for
4 hours. the specific latent heat(enthalpy) of fusion of ice is 0.33MJg^(−1)
b) How much ice would you expect to have melted at the end of the
four hours?
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