When a bimetallic bar made of copper and iron strips is heated, the bar bends toward the iron strip. The reason for this is
copper expands more than iron
Which of the following contracts most when the temperature is increased? Equal volumes of
ice water
When we enlarge a photograph of an iron ring, the image of the hole becomes
larger
Consider a sample of water at 0 degrees C. If the temperature is slightly increased, the volume of the water
decreases
When an iron ring is heated, the hole becomes
larger
Room temperature on the Kelvin scale is about
300K
Aluminum has a specific heat capacity more than twice that of copper. Place equal masses of aluminum and copper wire in a flame and the one to undergo the fastest increase in temperature will b
copper
Compared to a giant iceberg, a hot cup of coffee has
higher temperature, but less internal energy
Before ice can form on a lake, all the water in the lake must be cooled to
4 degrees C
The fact that a thermometer "takes its own temperature" illustrates
thermal equilibrium.
Heat energy is measured in units of
joules and calories
The moderate temperatures of islands throughout the world has much to do with water's
high specific heat.
Some molecules are able to absorb large amounts of energy in the form of internal vibrations and rotations. Materials composed of such molecules have
high specific heats
Pour a liter of water at 40 degrees C into a liter of water at 20 degrees C and the final temperature of the two becomes
at or about 30 degrees C.
The temperature at the bottom of Lake Tahoe, high in the Sierra Nevada Mountains in California, at this moment is
4 degrees c
Systems that are left alone, tend to move toward a state of
more entropy
A volume of air has a temperature of 0 degrees Celsius. An equal volume of air that is twice as hot has a temperature of
273 degrees C
Entropy measures
messiness
When a system does work and no heat is added to the system, its temperature
decreases
To wholly convert a given amount of heat energy into mechanical energy is
impossible regardless of the technique used
Suppose you put a closed, sealed can of air on a hot stove burner. The contained air will undergo an increase in
temperature and pressure
Suppose the temperature of the input reservoir in a heat engine doesn't change. As the sink temperature is lowered, the efficiency of the engine
increases
A hot dog pants
to help evaporation occur in its mouth and bronchial tract.
When liquids change to a solid state, they
release energy
When heat is added to boiling water, its temperature
does not change
For increased atmospheric pressure, the boiling temperature of a liquid
goes up
Increased air pressure on the surface of hot water tends to
prevent boiling
You can briefly touch a hot clothes iron with a bare wet finger because the wetness
absorbs energy in vaporizing.
provides an insulating layer after it changes state.
When a gas is changed to a liquid state, the gas
releases energy
Evaporation is a cooling process because
the more energetic molecules are able to escape the liquid
To melt 50 grams of 0-degree-Celsius ice requires
none of these
Compared to a glass of icewater with ice in it, a glass of plain ice-cold water without ice on a warm day will warm up
faster
f you want to cook eggs by boiling them while in the mountains, then compared to sea-level cooking, you should
boil the eggs for a longer time.
Food in a pressure cooker is cooked faster because of the
higher temp
When bringing water to a boil in the mountains, the time needed to reach the boiling point is
less than sea level
Wrapping a hot potato in aluminum foil significantly reduces the rate at which it cools by
evaporation
Your feet feel warmer on a rug than on your tile floor because your rug
is a better insulator than your tile.
Energy transfer by convection is primarily restricted to
fluids
Substances absorb heat energy by the process of
all of these
Metals are both good heat conductors and good electrical conductors because of the
looseness of outer electrons in metal atoms
An object will normally be a net radiator of energy when its temperature is
higher than its surroundings
Objects that radiate relatively well
absorb radiation relatively well.
Wrapping a hot potato in aluminum foil significantly reduces the rate at which it loses energy by
radiation
The higher the temperature of an object,
the shorter the wavelengths it radiates
Both black and white road surfaces absorb sunlight. At the end of a sunny day the warmer road surface will b
the black surface
Both black and white road surfaces radiate energy. At the end of a starry night the warmer road surface will be
the white surface
In a mixture of hydrogen gas, oxygen gas, and nitrogen gas, the molecules with the greatest average speed are those of
hydrogen
One of the main reasons one can walk barefoot on red-hot coals of wood without burning the feet has to do wit
low thermal conductivity of the coals
If a poor absorber of radiation were a good emitter, its temperature would be
less than its surroundings
A good reflector of radiation is
poor absorber of radiation