Exam 14: Heat

A 1500 W portable heater is needed to replace the heat lost through a circular window in the wall of a home. The window is made of a single pane of glass 0.30 cm thick. The thermal conductivity for the glass is 0.63 W/(m·K). The temperature inside the house is 20 °C and outside is −12 °C. What is the radius of the window?

200 joules of heat flows into a 35.0 g sample. If the temperature increases by 10.0 °C, then what is the specific heat capacity of the sample, in J/kg °C?

A metal rod is placed between two temperature sources so that heat can flow between them. One temperature is 90.0 °C and the other temperature is 25.0 °C. The length of the rod is 30.0 cm and the cross-sectional area is 10.0 cm². If 15.0 watts of heat flows between the hot temperature and the cold temperature, then what is the thermal conductivity for the metal?

What form of convection causes the onshore sea breeze in the day?

Radiant energy from the Sun reaches the Earth at a rate of 1.70 × 10¹⁷ W. When 30% of the radiant energy is reflected and 70% absorbed, the average temperature of the Earth's atmosphere is 253 K. If the atmosphere absorbed 100% of the solar radiant energy, then what would be the average temperature of the Earth's atmosphere?

The heat of fusion for ice at 0 °C is 333.7 kJ/kg, the specific heat of water 4.186 kJ/kg °C, and the heat of vaporization of water at 100 °C is 2,256 kJ/kg. What is the energy needed to vaporize 100 grams of ice at starting at 0 °C?

If the temperature of the sun is 5,800 K, then what is wavelength at which the blackbody radiation is a maximum?

A brass rod with a length of 20.0 cm is placed side by side with an aluminum rod with a length of 20.0 cm, and this system is placed between a hot temperature of 150 °C and a cold temperature of −10.0 °C. The thermal conductivities of the brass and the aluminum are 100 W/m °C and 230 W/m °C, respectively. The rods have the same cross-sectional area of 20.0 cm². What is the rate of heat flow from the hot temperature to the cold temperature?

The specific heat of ice is 2.10 kJ/kg °C, the heat of fusion for ice at 0 °C is 333.7 kJ/kg, the specific heat of water 4.186 kJ/kg °C, the heat of vaporization of water at 100 °C is 2,256 kJ/kg, and the specific heat of steam is 2.020 kJ/kg °C. What is the final equilibrium temperature when 40.0 grams of ice at 0 °C is mixed with 8.00 grams of steam at 120 °C?

The specific heat of ice is 2.10 kJ/kg °C, the heat of fusion for ice at 0 °C is 333.7 kJ/kg, the specific heat of water 4.186 kJ/kg °C, and the heat of vaporization of water at 100 °C is 2,256 kJ/kg. What is the final equilibrium temperature when 10.0 grams of ice at −15.0 °C is mixed with 3.00 grams of steam at 100 °C?

The outer surface of a wood-burning stove in a cabin is at a temperature of 150 °C. What is the wavelength at which the blackbody radiation is a maximum?

Which type of heat transfer is used in most automobile engines to carry excess heat away from the hot engine?

If the temperature of 2.000 moles of a monatomic ideal gas is increased by 50 °C, then what is the increase in the internal energy of the gas?

The heat of vaporization of water at 100.0 °C is 2,256 kJ/kg. What is the heat of vaporization of water in cal/g?

A jogger runs a kilometer in 8.30 minutes in still, dry air at a temperature of 25.0 °C. Her skin has a temperature of 35.0 °C and an exposed area of 1.00 m². If the convective coefficient is 22.0 W/m² °C, then what is the rate of heat flow due to convection from her skin to the air?

A rigid cubic box, 15 cm on a side, is filled with nitrogen gas (N₂) at standard temperature and pressure (0 °C and 1 atm). If 185 J of heat is added to the box, what is the final temperature of the gas?

A person lifts 10.00 N weights a vertical distance of 50.00 cm. How many times would they have to lift the weight to use 10.00 Calories of energy?

The intensity of solar radiation reaching the Earth is 1,340 W/m² when the temperature of the Sun is 5,800 K. If the temperature of the Sun increased by 10.00%, then what would be the intensity of solar radiation reaching the earth?

A 100 gram glass container contains 200 grams of water and 10 grams of ice all at 0 °C. A 200 gram piece of lead at 100 °C is added to the water and ice in the container. What is the final temperature of the system? (specific heat of ice = 2,000 J/kg °C, specific heat of water = 4,186 J/kg °C, heat of fusion of water = 333.7 kJ/kg, specific heat of glass = 837.2 J/kg °C, specific heat of lead = 127.7 J/kg °C)

A 100 gram glass container contains 200 grams of water and 5 grams of ice all at 0 °C. A 200 gram piece of lead at 100 °C is added to the water and ice in the container. What is the final temperature of the system? (specific heat of ice = 2,000 J/kg °C , specific heat of water = 4,186 J/kg °C, heat of fusion of water = 333.7 kJ/kg, specific heat of glass = 837.2 J/kg °C, specific heat of lead = 127.7 J/kg °C)