Exam 11: Energy in Thermal Processes Heat and Internal Energy

In cloud formation,water vapor turns into water droplets which get bigger and bigger until it rains.This will cause the temperature of the air in the clouds to:

How much heat energy is required to vaporize a 1.0-g ice cube at 0°C? The heat of fusion of ice is 80 cal/g.The heat of vaporization of water is 540 cal/g,and c_water = 1.00 cal/g⋅°C.

Dmitri places one end of a copper rod in a heat reservoir and the other end in a heat sink.By what factor is the rate of heat flow changed when the temperature difference between the reservoir and sink is tripled?

115 g of dry ice (solid CO₂)is dropped into a beaker containing 550 g of 78°C water.The dry ice converts directly to gas,leaving the solution.When the dry ice is gone,the final temperature of the water is 47°C.What is the heat of vaporization of solid CO₂? (c_water = 1.00 cal/g⋅°C) ​

The use of fiberglass insulation in the outer walls of a building is intended to minimize heat transfer through the wall by what process?

Of the planets with atmospheres,which is the warmest?

In a greenhouse,electromagnetic energy in the form of visible light enters the glass panes and is absorbed and then reradiated.What happens to this reradiated electromagnetic radiation from within the greenhouse?

A 1.8-m² Thermopane window is constructed,using two layers of glass 5.0 mm thick,separated by an air space of 6.0 mm.If the temperature difference is 22 °C from the inside of the house to the outside air,what is the rate of heat flow through this window? (Thermal conductivity for glass is 0.84 J/s⋅m⋅°C and for air 0.023 4 J/s⋅m⋅°C. )

What temperature increase is necessary to increase the power radiated from an object by a factor of 6? ​

Inside a house,stepping on a tile floor barefooted may feel almost cold,but stepping on carpet in an adjacent room feels comfortably warm.Why is this?

A slice of bread contains about 115 kcal.If specific heat of a person were 1.00 kcal/kg⋅°C,by how many °C would the temperature of a 65.0-kg person increase if all the energy in the bread were converted to heat? ​

The inside of a house is at 20°C on an early morning when the temperature outside is 15°C.The next morning the inside temperature is the same but the outside temperature is now 10°C.How much does the energy per unit time lost by conduction through the walls,windows,doors,etc. ,change for the house from the first morning to the second one?

On a sunny day at the beach,the reason the sand gets so hot and the water stays relatively cool is attributed to the difference in which property between water and sand?

If heat is flowing from a table to a block of ice moving across the table,which of the following must be true?

A 150-g block of copper is taken from a kiln and quickly placed into a beaker of negligible heat capacity containing 500 g of water.The water temperature rises from 10°C to 30°C.Given c_Cu = 0.10 cal/g⋅°C,and c_water = 1.00 cal/g⋅°C,what was the temperature of the kiln?

What is the temperature increase of 5.0 kg of water when heated by an 1,000-W immersion heater for 6 min? (c_w = 4 186 J/kg⋅°C) ​

Who demonstrated that when heat is gained or lost by a system during some process,the gain or loss can be accounted for by an equivalent quantity of mechanical work done on the system?

An inventor develops a stationary cycling device by which an individual,while pedaling,can convert all of the energy expended into heat for warming water.What minimum power must be generated if 300 g water (enough for 1 cup of coffee)is to be heated in 12 min from 18°C to 94°C? (1 cal = 4.186 J,the specific heat of water is 4 186 J/kg⋅°C) ​

A 2.00-kg copper rod is 49.00 cm long at 23°C.If 40,000 J are transferred to the rod by heat,what is its change in length? c_copper = 387 J/kg⋅°C and α_copper = 17 × 10−⁶/°C. ​

The thermal conductivity of silver is 427 J/s⋅m⋅°C and of copper is 397 J/s⋅m⋅°C.A rod of each material is used as a heat conductor.If the rods have the same geometry and are used between the same temperature differences for the same time interval,what is the ratio of the heat transferred by silver to the heat transferred by the copper?