Physics Final Conceptual Questions

Absolute zero on the Celsius temperature scale is -273.15C. What is absolute zero on the Fahrenheit temperature scale?

-459.67F

Note the following six properties: (1) # of Molecules (3) Temperature (5) Latent Heat (2) Moment of Inertia (4) Pressure (6) Volume Which four of the listed properties are needed to describe an ideal gas?

1, 3, 4, 6

Two identical solid spheres have the same temperature. One of the spheres is cut into two identical pieces. These two hemispheres are then separated. The intact sphere radiates an energy Q during a given time interval. During the same interval, the two hemisphere radiate a total energy Q'. What is the ratio Q'/Q?

1.5

Complete the following statement: The atomic mass unit (u) is defined so that 1 u is exactly equal to the mass of...

1/12 of a carbon-12 atom

The ends of a cylindrical steel rod are maintained at different temperatures. The rod conducts heat from one end to the other at a rate of 10cal/s. At what rate would a steel rod twice as long and twice the diameter conduct heat between the same two temperatures?

20cal/s

The coefficient of linear expansion of a certain solid is 9x10^-6/C. Assuming this solid behaves like most solids, what is its coefficient of volume expansion?

27x10^-6/C

Which of the following temperatures is approximately equal to "room temperature?"

293K

Complete the following statement: A temperature decrease of 30C is equal to a temperature decrease of

30K

Which object will emit more electromagnetic radiation than it absorbs from its surroundings?

A 200C copper coin in a beaker of water a 98C.

Which one of the following objects, all initially at the same temperature, will be more efficient in losing heat?

A dull black box in air

Which of the following is NOT an example of convection?

A person gets a suntan on a beach.

A gas molecule with a molecular mass of 32.0 u has a speed of 325 m/s. What is the temperature of the gas molecule?

A temperature cannot be assigned to a single molecule.

Which one of the following materials is the POOREST thermal conductor?

Air

The specific heat capacity of iron is approximately half that of aluminum. Two balls of equal mass, one made of iron and the other of aluminum, both at 80C, are dropped into a thermally insulated jar that contains an equal mass of water at 20C. Thermal equilibrium is eventually reached. Which one of the following statements concerning the final temperatures is true?

Both balls will reach the same final temperature.

A beaker of water is placed on a Bunsen burner. As the lower layers of water are heated, they become less dense and rise. This permits cooer layers to move downward and be heater. Eventually, the water boils. Which method(s) of heat transfer is (are) primarily responsible for boiling the sample?

Both conduction and convection.

The space between the inner walls of a thermos bottle is evacuated to minimize heat transfer by...

Conduction and Convection

Which one of the following materials is the BEST thermal conductor?

Diamond

Which one of the following statements concerning diffusion is true?

Diffusion occurs in solids and fluids.

Which one of the following statements concerning emissivity is false?

Emissivity depends on the surface area of the object.

Complete the following statement: Bimetallic strips used as adjustable switches in electric appliances consist of metallic strips that must have different...

Expansion coefficients

Complete the following Statement: When a substance undergoes fusion it...

Freezes

Which of the following statements best explains why gases are not commercially sold by volume?

Gas volume depends on temperature and pressure.

Under which of the following conditions would you expect real gases to approach ideal behavior?

High temperature and low pressure.

Which of the following statements concerning the mole is false?

One mole of a substance has the same mass as one more of any other substance.

Complete the following statement: The transfer of heat by convection will occur...

Only in the presence of a liquid or a gas.

Complete the following statement: The internal energy of an ideal monatomic gas is...

Proportional to the Kelvin temperature of the gas.

Complete the following statement: Most of the heat that is lose to space from the earth occurs by

Radiation

Complete the following statement: The interior of a thermos bottle is silvered to minimize heat transfer due to...

Radiation

Two cubes, one silver and one iron, have the same mass and temperature. A quantity Q of heat is removed from each cube. Which one of the following properties causes the final temperatures of the cubes to be different?

Specific heat capacity

Which would cause a more serious burn: 30g of steam or 30g of liquid water, both at 100C; and why is this so?

Steam, because of its latent heat of vaporization.

Complete the following statement: When solid NH passes directly to the gaseous state it is said to...

Sublime

Three thermometers are placed in a closed, insulated box and are allowed to reach thermal equilibrium. One is calibrated in Fahrenheit degrees, one in Celsius degrees, and one in Kelvins. The Celsius thermometer reads -40C and the Kelvin thermometer reads 233K. Which one of the following statements is necessarily true?

The Fahrenheit thermometer must read -40F.

Three thermometers are in the same water bath. After thermal equilibrium is established, it is found that the Celsius thermometer reads 100C, the Fahrenheit thermometer reads 212F, and the Kelvin thermometer reads 273K. Which one of the following statements is the most reasonable conclusion?

The Kelvin thermometer is incorrect.

The volume of a carbon dioxide bubble rising in a glass of beer is observed to nearly double as the bubble rises from the bottom to the top of the glass. Why, according to our textbook, does the volume nearly double?

The amount of carbon dioxide in the bubble increases.

Which one of the following properties of a gas is not consistent with kinetic theory?

The average speed of the gas molecules is smaller at high temperatures.

Complete the following statement: The absolute temperature of an ideal gas is directly proportional to...

The average translational kinetic energy of the gas.

Which one of the following properties count NOT be used as a temperature sensitive property in the construction of a thermometer?

The change in mass of a solid.

Which one of the following factors is directly responsible for the pressure exerted by a confined gas?

The collision of gas molecules with the sides of the containing vessel.

The sun continuously radiates energy into space, some of which is intercepted by the earth. The average temperature of the surface of the earth remains about 300K. Why doesn't earth's temperature rise as it intercepts the sun's energy?

The earth radiates an amount of energy into space equal to the amount it receives.

Suppose you are sitting next to a fireplace in which there is a fire burning. One end of a metal poker has been left in the fire. Which one of the following statements concerning this situation is true?

The end of the poker that is not in the fire is warmed through conduction.

Which one of the following statements concerning Stefan-Boltzmann equation is true?

The equation can be used to calculate the power absorbed by any surface.

Complete the following statement: The term heat most accurately describes...

The flow of energy due to a temperature difference.

Which one of the following phrases is an example of sublimation?

The fumes produced by moth balls.

An ordinary mercury thermometer at room temperature is quickly placed in a beaker of hot water. The mercury column is observed to drop slightly before it rises to the final equilibrium temperature. Which one of the following statements is the best explanation for this behavior?

The glass envelope expands before the heat reaches the mercury.

Complete the following statement: A bicycle tire explodes after lying in the hot afternoon sun. This is an illustration of...

The ideal gas law.

Two ends of an iron rod are maintained at different temperatures. The amount of heat that flows through the rod by conduction during a given time interval does NOT depend on...

The mass of the iron rod.

Complete the following statement: The pressure exerted by a monatomic, ideal gas on the walls of its containing vessel is a measure of

The molecular kinetic energy per unit volume.

Consider two ideal gases, A and B, at the same temperature. The RMS speed of the molecules of gas A is twice that of gas B. How does the molecular mass of A compare to that of B?

The molecular mass of A is one fourth that of B.

Which one of the following statements concerning a collection of gas molecules at a certain temperature is true?

The molecules have a range of kinetic energies.

Which one of the following statements best explains why convection does not occur in solids?

The molecules in a solid are not free to move throughout the volume of the solid.

On a warm summer day, the relative humidity is 30% when the temperature is 32C. Which one of the following statements is true if the temperature suddenly decreases to 26C and all other conditions remain the same?

The relative humidity will increase.

Heat is added to a substance, but its temperature does not rise. Which one of the following statements provides the best explanation for this observation?

The substance undergoes a change of phase.

Heat is added to a sample of water in an insulated container. Which one of the following statements is necessarily true?

The type of change that will occur depends on the original temperature of the water.

Which of the following processes does not occur during the convective transfer of heat within a container of air?

The volume of a warmed part of the air is reduced and its density increases.

Which one of the following statements explains why it is difficult to measure the coefficient of volume expansion for a liquid?

The volume of the containing vessel will also increase.

A sample of neon gas at 20 °C is confined to a cylinder with a movable piston. The gas is then heated until its pressure is doubled. What is the final temperature of the gas?

This cannot be found since the final and initial volumes are unknown.

Which one of the following statements is the best explanation for the fact that metal pipes that carry water often burst during cold winter months?

Water expands upon freezing while the metal contracts at lower temperatures.

If a beaker of water is placed under a broiler so that the heating coil is above the beaker. It is observed that only the surface layer boils. The water at the bottom of the beaker remains close to the initial temperature of the water. Which of the following statements is the most reasonable conclusion to be drawn from these observations?

Water is a poor conductor of heat.

A physics student looks into a microscope and observes that small particles suspended in water are moving about in an irregular motion. Which of the following statements is the best explanation for this observation?

Water molecules strike the particles giving them the same average kinetic energy as the water.

The units of heat are equivalent to those of which of the following quantities?

Work