A class of 10 students taking an exam has a power output per student of about 200 W. Assume the initial temperature of the room is 20°C and that its dimensions are 6.0 m by 15.0 m by 3.0 m. What is the temperature of the room at the end of 1.0 h if all the energy remains in the air in the room and none is added by an outside source? The specific heat of air is 837 J/kg . °C, and its density is about 1.3 x 10-3 g/cm3.

Rubbing your hands together warms them by converting work into thermal energy. a. If a woman rubs her hands a total of 19 times (forward and backwards count separately), at a distance of 7.75 cm per rub, and with an average frictional force of 39 N, what is the temperature increase of her hands, in degrees Celsius? The mass of tissues warmed is only 0.100 kg, mostly in the palms and fingers, and the heat capacity of her hands is 3500 J/(kg⋅°C).

In an electrically heated home, the temperature of the ground in contact with a concrete basement wall is 14.0 °C. The temperature at the inside surface of the wall is 21.4 °C. The wall is 0.12 m thick and has an area of 7.7 m2. Assume that one kilowatt hour of electrical energy costs $0.10. How many hours are required for one dollar's worth of energy to be conducted through the wall? Number Units the tolerance is +/-2%

Suppose you want to raise the temperature of a 0.18-kg piece of ice from -20.0°C to 130°C. The heat of fusion is Lf = 334 kJ/kg, and the heat of vaporization is Lv = 2256 kJ/kg. In this problem, take 1520 J/kg⋅°C as the specific heat of steam, and 2090 J/kg⋅°C as the specific heat of ice.  a.)   How much heat, in kilocalories, must be transferred for this to happen, including the energy needed for phase changes?    b.)  How much time, in seconds, is required to do this, assuming a constant 20.0 kJ/s rate of heat transfer?

Kerepakupai Vena in Venezuela, more commonly known as Angel Falls, is the world's highest waterfall with a height of 979 m and 47 different plunges. The longest plunge (for the water) is 807 m. At the bottom of the fall, the kinetic energy of the water is converted into thermal energy. This results in a temperature increase of the water. If the water has a temperature of 21.9°C when it gets to the bottom of the plunge, what was the temperature at the top of the plunge? The specific heat of water is 1.00 kcal/(kg · °C).

7. (a) What is the heat capacity of a system consisting of a 0.3600 kg brass cup filled with 0.05000 kg of water? in kJ/K (b) What is the heat capacity of a system consisting of 7.700 kg of water in a 0.8800 kg aluminum bucket? in kJ/k

In an insulated container, you combine hot metal with ice. The ice starts at -20 degree C. The copper starts at 900 degree C. When 15 kg of the copper is combined with an unknown amount of ice, the system reaches equilibrium as soon as all of the ice has boiled to become steam. What is the final temperature of the copper?

A Styrofoam box has a surface area of 0.81 m² and a wall thickness of 2.0 cm. The temperature of the inner surface is 5.0°C, and the outside temperature is 26°C. If it takes 8.5 h for 5.0 kg of ice to melt in the container, determine the thermal conductivity of the Styrofoam. (Assume the ice is at a temperature of 0°C.) W/m · °C

You drop an ice cube into an insulated bottle full of water and wait for the ice cube to completely melt. The ice cube initially has a mass of 70.0 g and a temperature of 0°C. The water (before the ice cube is added) has a mass of 880 g and an initial temperature of 20.0°C. What is the final temperature (in °C) of the mixture? (Assume no energy is lost to the walls of the bottle, or to the environment.)  ?°C

A closed box is filled with dry ice at a temperature of -88.3 oC, while the outside temperature is 18.8 oC. The box is cubical, measuring 0.309 m on a side, and the thickness of the walls is 3.80 × 10-2 m. In one day, 3.62 × 106 J of heat is conducted through the six walls. Find the thermal conductivity of the material from which the box is made.