Question

The temperature of the water deceases to from 20 C to 0 C in 10 minutes. The mass of water is 200 grams. (specifi heat capacity of water = 4200J kg -1 K-1

i) Calculate the energy lost by the water when temperature decreases to 0 C

Answer 1

Solution.

$t_1=20^oC;$

$t_2=0^oC;$

$c=4200Jkg^{-1}K^{-1};$

$m=200g=0.2kg;$

$\Delta W=cm\Delta t;$

$\Delta W=4200Jkg^{-1}K^{-1}\sdot0.2kg\sdot20K=16800J;$

Answer:$\Delta W=16800J.$