120 grams of boiling water (temperature 100° C, heat capacity 4.2J/gram/K) are poured into an aluminum pan whose mass is 1100 gramsand initial temperature 22° C (the heat capacity of aluminum is 0.9J/gram/K).
(a) After a short time, what is the temperature of the water?
Tfinal = C
(b) What simplifying assumptions did you have to make?
-Energy transfer between the system (water plus pan) and thesurroundings was negligible during this time.
-The heat capacities for both water and aluminum hardly change withtemperature in this temperature range.
-The thermal energy of the aluminum doesn't change.
-The thermal energy of the water doesn't change.
(c) Next you place the pan on a hot electric stove. While the stoveis heating the pan, you use a beater to stir the water, doing 26432J of work, and the temperature of the water and pan increases to77.8° C. How much energy transfer due to a temperature differencewas there from the stove into the system consisting of the waterplus the pan?
Q = J
120 grams of boiling water (temperature 100° C, heat capacity 4.2J/gram/K) are poured into an aluminum pan whose mass is 1100 gramsand initial temperature 22° C (the heat capacity of aluminum is 0.9J/gram/K).
(a) After a short time, what is the temperature of the water?
Tfinal = C
(b) What simplifying assumptions did you have to make?
-Energy transfer between the system (water plus pan) and thesurroundings was negligible during this time.
-The heat capacities for both water and aluminum hardly change withtemperature in this temperature range.
-The thermal energy of the aluminum doesn't change.
-The thermal energy of the water doesn't change.
(c) Next you place the pan on a hot electric stove. While the stoveis heating the pan, you use a beater to stir the water, doing 26432J of work, and the temperature of the water and pan increases to77.8° C. How much energy transfer due to a temperature differencewas there from the stove into the system consisting of the waterplus the pan?
Q = J
