7.1 A twelve pack of your favorite beverage (12 fl. oz. cans) is placed in a coo

Question

7.1 A twelve pack of your favorite beverage (12 fl. oz. cans) is placed in a cooler at 70F. How much heat must be removed (Btu’s) to cool the beverages to 34F?

7.2 Seven pounds of ice at 20F is placed in the cooler with the beverages in problem 7.1. Assume no heat is gained from the environment outside of the cooler. What is the equilibrium temperature (F) of the beverages and the ice?

7.3 If the rate of heat gained by the cooler (in problems 7.1 and 7.2) from the surrounding environment is 50.0 Btu/hr., how long (hr.) will the ice in the cooler last? Assume the beverages are placed in the cooler at 32F.

7.4 A runner consumes 1.0 L of water during an event. What has a greater cooling influence on the human body, the cold temperature of the water (5C), or evaporation of this water from the skin of the runner? Justify your answer with supporting calculations.

Explanation / Answer

7.1

Temperature drop = 70 - 34 = 36 F = 20 C

Mass = 12 fl. oz = 354.88 g

C for beverage = 4.2 J/g-K (assumed water)

Soheat removed = mCT = 354.88*4.2*20 = 29809 J = 29809/1055 BTU = 28.26 BTU

7.2

Related Questions

Navigate

• Browse (All)
• Browse 7
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.