our camp fuel has an energy density of 50 kJ/g. Assuming perfect efficiency how much fuel does it take to melt 500 grams of ice starting at -10˚C and then raise it just to 100 degrees (but not boil it dry)? How much fuel do you save if the water started out as a liquid at 0˚C instead of ice at -10˚C?

A car tile contains 0.0380 m3 of air at a pressure of 2.20105 Pa (about 32 psi). How much more internal energy does this gas have than the same volume has at zero gauge pressure (which is equivalent to normal atmospheric pressure)?

A refrigerator has 18.0 kJ of work done on it while 115 kJ of energy is transferred from inside its interior. What is its coefficient of performance? (a) 3.40 (b) 2.80 (c) 8.90 (d) 6.40 (e) 5.20

If a gas is compressed isothermally, which of the following statements is true? (a) Energy is transferred into the gas by heat. (b) No work is done on the gas. (c) The temperature of the gas increases, (d) The internal energy of the gas remains constant, (e) None of those statements is true.

When 400 J of heat are slowly added to 10 mol of an ideal monatomic gas, its temperature rises by 10 . What is the work done on the gas?

A refrigerator has 18.0 kJ of work clone on it while 115kJ of energy is transferred from inside its interior. What is its coefficient of performance? (a) 3.40 (b) 2.80 (c) 8.90 (d) 6.40 (e) 5.20

Repeat the preceding problem for nitrogen molecules at 295 K.

(a) How much food energy (in kcal) will a man metabolize in the process of doing 36.7 k) of work with an efficiency of 5.75%? kcal (b) How much heat transfer (in kcal) occurs to the environment to keep his temperature constant? kcal Explicitly show how you follow the steps in the Problem-Solving Strategy for Thermodynamics.

Consider an adiabatic humidification system shown below. The humidifying efficiency is E = 0.8, the air flow rate is 2 L/s,m² and the temperature rise in the supply air fan (2→3) is 1°C. T room The heat load into the room q [W/m²] is defined on the basis of the room temperature as: q = 35 Troom < 22 °C – 22 q =35×|1-room 18 22 °C < Troom< 40 °C q = 0 Troom2 40 °C Based on the room's hourly heat balance calculate the maximum room temperature (Troom) and the number of hours (within a 72 hour-period), when the room temperature exceeds 25°C. Examine both the case with the humidifier (State 2 + State 1) and without it (State 2 = State 1). Hourly inlet temperature and relative humidity (State 1) is provided as a separate data file (LA3_Data).

Over the course of a day, 4.0 kg of water evaporates from the leaves of a corn plant. a) How much energy is required to evaporate the water? (Assume that the temperature of the leaves is 30C.) b) If the plant is active for 12 hours, how much power does this correspond to? You can think of this as the necessary power to drive transport in the plant.