How could I find the rate of heat absorption?

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SUMMARY

The rate of heat absorption by a refrigerator can be calculated using the formula Rate of Heat Absorbed = Q/t, where Q is the heat removed and t is the time. In this case, the heat removed (Q) is calculated using Q = mcΔT, where m is the mass of water (2.15 kg), c is the specific heat capacity (4.2 J/kg°C), and ΔT is the temperature change (21.5°C to 0°C). The initial calculation yielded a rate of 2.6 x 10^-2 Js-1, but the correct answer for the total heat absorption rate, including the phase change from water to ice, is 1.27 x 10^2 Js-1.

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Homework Statement



At what rate is a refrigerator absorbing heat if 2·15 kg of water at 21·5 °C is just frozen in 2·00 h?



Homework Equations



Q = mL
Q = mcΔT



The Attempt at a Solution



Rate of Heat Absorbed = Q/t
= mcΔT/t
= (2.15*4.2*21.5)/(2*60*60)
= 2.6*10^-2

The actual answer should be 1·27x10^2 Js-1
 
Last edited by a moderator:
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You calculated the rate to lower the temperature of the water from 21.5 C to 0 C. After you remove this heat, the water will still be liquid. How much more heat do you have to remove to turn it into ice?
 

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