1. A college student produces about 119 kcal of heat per hour on the average. What is the rate of energy production in joules? kJ/h
2. How many kilocalories of heat does an expenditure of 135 kJ produce? kcal
3. A pound of body fat stores an amount of chemical energy equivalent to 3500 Cal. When sleeping, the average adult burns or expends about 0.45 Cal/h for every pound of body weight. How many Calories would a181 lb person burn during 6 hours of sleep? (Note that 1 Cal = 1 kcal.) Cal
4. A pound of body fat stores an amount of chemical energy equivalent to 3,500 Cal. When sleeping, the average adult burns or expends about 0.42 Cal/h for every pound of body weight.
How long would the person have to sleep continuously to lose 1 lb of body fat? (Assume the person weighs 160 lb.) h
5. On a brisk walk, a person burns about 330 Cal/h. At this rate, how many hours of brisk walking would it take to lose 1 lb of body fat? (A pound of body fat stores an amount of chemical energy equivalent to3,500 Cal.) h
6. On a brisk walk, a person burns about 316 Cal/h. If the brisk walk were done at 3.4 mi/h, how far would a person have to walk to burn off 1 lb of body fat? (A pound of body fat stores an amount of chemical energy equivalent to 3,500 Cal.) mi
7. How much heat in kcal must be added to 0.59 kg of water at room temperature (20°C) to raise its temperature to 40°C? kcal
8. (a) How much energy is necessary to heat 8.0 kg of water from room temperature (20°C) to its boiling point? (Assume no energy loss.) kcal
(b) If electrical energy were used, how much would this cost at 29¢ per kWh? ¢
9. How much heat is necessary to change 485 g of ice at -19°C to water at 20°C? kcal
10. A quantity of steam (250 g) at 127°C is condensed, and the resulting water is frozen into ice at 0°C. How much heat was removed? kcal