Q #1 Suppose a woman does 363 J of work and dissipates 9,054 J of heat in the process.
(a) What is the decrease in her internal energy, assuming no change in temperature or consumption of food? (That is, there is no other energy transfer.)
kcal
(b) What is her efficiency?
%
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Q # 2 (a) How long will the energy in a 122 kcal cup of yogurt last in a woman doing work at the rate of 155 W with an efficiency of 20% (such as in leisurely climbing stairs)?
min
(b) Does the time found in part (a) imply that it is easy to consume more food calories in one day than you can reasonably expect to work off with an hour of exercise?
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Q # 3 A lead block of mass 8.6 kg is originally at a temperature of 26°C and 1 atm. It is then heated to a temperature of 60°C without any change in pressure. The specific heat of lead is 128 J/(kg · °C), its density is 
104
(a) Determine the work done by the lead block.
J
(b) How much heat energy is transferred during this process?
J
(c) What is the increase in internal energy of the system?
J
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Q #4 The engine of a large ship does 1010
(a) How much waste heat is produced?
J
(b) How many barrels of fuel are consumed if each barrel produces 109
barrels—————————–
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Q# 5 Determine the efficiency of a Carnot engine if the work it does is 8.17 times less than the heat that flows into the system.
%
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Q 6 # When 105
°C-
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Q # 7 (a) During a process, the increase in entropy of a system is 3638 J/K, and the energy that becomes unavailable for doing work is zero. Which of the following statements is correct?
(b) By how much does the entropy of the surroundings change?
J/K
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