Conceptual Physics Chapter 14 – Flashcards

When a party balloon is compressed to one-third its volume, gas pressure in the balloon _______. a. is also one-third b. remains the same if temperature doesn't change c. doubles d. triples

A column of mercury 76 cm tall has a weight that is equal to _______. a. that of a column of water 10.3 meters tall b. normal atmospheric pressure c. the weight of Earth's atmosphere d. 13.6 times the density of water

A 1-kg balloon at equilibrium in the air is buoyed up with a force of _______. a. 1 kilogram b. 12 newtons c. 10 newtons d. 1 newton

A helium-filled balloon will reach its maximum altitude when _______. a. its weight equals the weight of displaced air b. it can no longer displace its own weight of air c. its density exceeds that of the surrounding air d. it displaces a greater weight of air than its own weight

When the speed of a fluid increases, internal pressure in the fluid _______. a. remains constant b. increases c. decreases d. increases as the square of the increase

Air pressure over the surface of a bird's wings decreases when _______. a. turning motion is executed b. the wing is tilted downward c. air speed decreases there d. air speed increases there

The energy source responsible for the motion of molecules that make up the atmosphere is a. solar power. b. the pressure caused by the weight of air. c. their own natural kinetic energy. d. atmospheric tides.

A plasma differs from a gas in that a. it is electrically conducting. b. its molecules are farther apart. c. its atoms are boosted to higher atomic numbers. d. it is hotter than a gas. e. all of these

Atmospheric molecules do not fly off into outer space because of a. cohesive forces. b. their relatively high speeds. c. earth gravitation. d. their relatively low densities.

Atmospheric pressure is caused by the a. temperature of the atmosphere. b. effect of the sun's energy on the atmosphere. c. weight of the atmosphere. d. density of the atmosphere.

A balloon is buoyed up with a force equal to the a. density of surrounding air. b. weight of the balloon and contents. c. weight of air it displaces. d. atmospheric pressure. e. all of these

As a helium-filled balloon rises in the air, it becomes a. bigger. b. heavier. c. more dense. d. all of these e. none of these

The air in this room has a. mass. b. weight. c. energy. d. all of these e. none of these

The faster a fluid moves, the a. less its internal pressure. b. greater its internal pressure. c. internal pressure is unaffected.

About how high can water be theoretically lifted by a vacuum pump at sea level? a. 10.3 m b. more than 10.3 m c. less than 10.3 m

Gas pressure inside an inflated stretched balloon is actually a. equal to air pressure outside the balloon. b. less than air pressure outside the balloon. c. greater than air pressure outside the balloon. d. impossible to determine without knowing the type of gas.

A helium-filled balloon released in the atmosphere will rise until a. atmospheric pressure on the bottom of the balloon equals atmospheric pressure on the top of the balloon. b. the pressure inside the balloon equals atmospheric pressure. c. the balloon and surrounding air have equal densities. d. all of these e. none of these

When gas in a container is squeezed to half its volume, its density a. quadruples. b. halves. c. remains the same. d. doubles.

A swimmer cannot use a long hose to snorkel more than a meter deep because air a. tends to liquefy in the snorkel tube. b. in the lungs cannot easily be expelled. c. at the surface will not freely enter the higher-pressure region in the compressed lungs. d. is buoyed up leaving the swimmer breathless. e. all of these

In a vacuum, an object has no a. buoyant force. b. temperature. c. mass. d. weight. e. all of these

In a vacuum a marshmallow becomes a. smaller. b. larger. c. a hollow shell. d. flat. e. none of the above choices

Which of the following bodies is comprised mostly of plasma? a. Sun b. Moon c. Earth d. all of these e. none of these

If you release a ball inside a freely falling elevator, it stays in front of you instead of "falling to the floor" because you, the ball, the elevator, and the air in the elevator are all in free fall. If you similarly release a helium-filled balloon, the balloon will a. slowly fall. b. press against the floor. c. slowly rise. d. press against the ceiling. e. also stay in front of you.

Suppose you are standing on a weighing scale and all of a sudden the atmosphere vanished. The reading on the scale would a. quickly reduce to zero. b. remain the same. c. increase. d. decrease.

An umbrella tends to move upwards on a windy day principally because a. air gets trapped under the umbrella, warms, and rises. b. buoyancy increases with increasing wind speed. c. air pressure is reduced over the curved top surface. d. all of these

If you made a barometer with water instead of mercury, you would have to use a tube that is 13.6 times taller. Why?

What pressure is exerted against bodies immersed in the atmosphere.

It results from the weight of air pressing down from above.

At sea level, atmospheric pressure is about

Any device that measures atmospheric pressure.

The product of pressure and volume is a constant for a given mass of confined gas, as long as temperature remains unchanged: P₁V₁ = P₂V₂

An object in the air is buoyed up with a force equal to the weight of displaced air.

When the speed of a fluid increases, internal pressure in the fluid decreases.

An electrified gas containing ions and free electrons.