Find the temperature differnce if 50 kg of water absorbs 500 kilo joule of heat
Answers
Answer:Strategy
The pan and the water are always at the same temperature. When you put the pan on the stove, the temperature of the water and the pan is increased by the same amount. We use the equation for the heat transfer for the given temperature change and mass of water and aluminum. The specific heat values for water and aluminum are given in Table 1.
Solution
Because water is in thermal contact with the aluminum, the pan and the water are at the same temperature.
Calculate the temperature difference:
ΔT = Tf − Ti = 60.0ºC.
Calculate the mass of water. Because the density of water is 1000 kg/m3, one liter of water has a mass of 1 kg, and the mass of 0.250 liters of water is mw = 0.250 kg.
Calculate the heat transferred to the water. Use the specific heat of water in Table 1:
Qw = mwcwΔT = (0.250 kg)(4186 J/kgºC)(60.0ºC) = 62.8 kJ.
Calculate the heat transferred to the aluminum. Use the specific heat for aluminum in Table 1:
QAl = mAlcAlΔT = (0.500 kg)(900 J/kgºC)(60.0ºC) = 27.0 × 104 J = 27.0 kJ.<
Compare the percentage of heat going into the pan versus that going into the water. First, find the total transferred heat:
QTotal = Qw + QAl = 62.8 kJ + 27.0 kJ = 89.8 kJ.
Thus, the amount of heat going into heating the pan is
27.0
kJ
89.8
kJ
×
100
%
=
30.1
%
and the amount going into heating the water is
62.8
kJ
89.8
kJ
×
100
%
=
69.9
%
Explanation: