Reference no: EM132583005

1. A machinist wishes to insert a copper rod with a diameter of 7 mm into a hole with a diameter of 6.995 mm. By how much would the machinist have to lower the temperature (in °C) of the rod to make it fit the hole?

2. As a gasoline engine is running, an amount of gasoline containing 14,800 J of chemical potential energy is burned in 1 s. During that second, the engine does 3,700 J of work.

(a) What is the engine's efficiency (in percent)?

(b) The burning gasoline has a temperature of about 5,000°F (3,000 K). The waste heat from the engine flows into air at about 90°F (305 K). What is the Carnot efficiency (in percent) of a heat engine operating between these two temperatures?

3. An irreversible process takes place by which the entropy of the universe increases by 1.74 J/K. If the temperature of the environment in which the process occurred is 210 K, how much energy (in J) was made unavailable for useful work as a result?

4. A lead vat is 15 m long at room temperature (20°C). How much longer is it when it contains boiling water at 1 atm pressure?

5. An aluminum wing on a passenger jet is 32 m long when its temperature is 28°C. At what temperature would the wing be 6 cm (0.06 m) shorter?

6. Air in a balloon does 27 J of work while absorbing 92 J of heat. What is its change in internal energy?

7. An apartment has the dimensions 13 m by 7 m by 4 m. The temperature is 30°C, and the relative humidity is 59 percent. What is the total mass (in kg) of water vapor in the air in the apartment?