Physics 101 Exam 2(FINAL)

When an air bubble rises in water, what happens to its density?

The bubble's density decreases.

Buoyant force acts upward on a submerged object because

pressure against its bottom is greater than pressure against its top.

To multiply an applied force while using a simple hydraulic lift, your force should be applied to the

small-diameter piston.

The centers of gravity of the three trucks parked on a hill are shown by the X's. Which truck(s) will tip over?

the leftmost truck

After a rock thrown straight up reaches the top of its path and then falls a short distance, its acceleration is (neglect air resistance)

the same as at the top of its path

If Alex wishes to rotate his skateboard, then he must apply a

torque.

A dam is thicker at the bottom than at the top mainly because

water pressure increases with depth.

The density of a submerged submarine at rest (in the middle of water not all the way down to the bottom of the ocean) is about the same as the density of

water.

What is the weight of water displaced by a 100-ton floating ship?

100 tons

A ball is thrown horizontally from a cliff at a speed of 13 m/s. What is its speed one second later? (you can ignore air resistance)

16.4 m/s

A projectile is fired straight upward at 146 m/s. How fast is it moving at the instant it reaches the top of its trajectory? (ignore air resistance).

16.4 m/s

The circumference of a bicycle wheel is 2 meters. If it rotates at 1 revolution per second then its linear speed is

2 m/s.

The rock has a mass of 3 kg. What is the mass of the measuring stick if it is balanced by a support force at the one-quarter mark?

3 kg

What is the weight of a cubic meter of cork? (For the density of cork, use 500 kg/m3.)

5000 N

Would a bottle of helium gas weigh more or less than an identical bottle filled with air at the same pressure?

A helium filled bottle will weigh less than an equal volume of air.

In a deep dive, a whale is appreciably compressed by the pressure of the surrounding water. What happens to the whale's density?

Its density increases.

The Moon does not crash into Earth because

Moon has a sufficient tangential speed.

What change in pressure occurs in a party balloon that is squeezed to one-third its volume with no change in temperature?

Pressure increases to three times its original pressure.

A block of aluminum with a mass of 1 kg is placed in a beaker of water filled to the brim. Water overflows. The same is done in another beaker with a l kg block of lead. Does the lead displace more, less, or the same amount of water? (lead is more dense than aluminum).

The aluminum block displaces more water.

When an air bubble rises in water, what happens to its mass?

The bubble's mass does not change.

When an air bubble rises in water, what happens to its volume?

The bubble's volume increases.

Would a fish float to the surface, sink, or stay at the same depth if the gravitational field of the Earth increased?

The fish would stay at its prior level in water.

An automobile speedometer is configured to read speed proportional to the rotational speed of its wheels. If larger wheels, such as those of snow tires, are used, will the speedometer reading be high or low - or no different?

The speedometer will read too low

A dropped ball gains speed because

a gravitational force acts on it.

The famous Leaning Tower of Pisa doesn't topple over because its center of gravity is

above its base.

When boarding an airplane you bring a bag of chips. While in flight the bag puffs up, because

air pressure in the air-tight bag is greater than cabin air pressure.

In drinking soda or water through a straw, we make use of

atmospheric pressure

Would it be slightly more difficult to draw soda through a straw at sea level or on top of a very high mountain?

atop a mountain,because the atmospheric pressure is less.

A bubble of air released from the bottom of a lake

becomes larger as it rises.

A very massive object A and a less massive object B move toward each other under the influence of gravity. Which force, if either, is greater?

both forces are the same.

A ball rolls off the edge of a table at the same time another ball drops vertically from the same table. The ball to hit the floor first is the

both hit at the same time

A fish normally displaces its own

both of these

When air resistance affects the motion of projectiles, they don't travel

both of these (as high, as far)

As a high-altitude balloon rises higher into the atmosphere, it undergoes a decrease in

density.

While an airplane flies at 40 m/s at an altitude of 500 meters, the pilot drops a heavy package that falls to the ground. Neglecting air drag, about where does the package land relative to the plane flying above?

directly beneath the plane

If a turntable's rotational speed is doubled, then the linear speed of a pet hamster sitting on the edge of the record will

double.

When a gas in a container is squeezed to half its volume with no change in temperature, the gas pressure

doubles.

When a gas in a container is squeezed to half its volume, its density

doubles.

A floating ice cube contains small pieces of iron. The water level after melting will

fall.

A ball is tossed upward. Neglecting air drag, the acceleration along its path is

g downward.

A scale from which a rock is suspended reads 5 N when the rock is out of water and 3 N when the rock is submerged. The density of the rock is

greater than the density of water

When you float in fresh water, the buoyant force that acts on you is equal to your weight. When you float higher in the denser water of the Dead Sea, the buoyant force that acts on you is

greater than your weight

If you hold two objects that have the same weight density, then they

have equal mass densities

Jane lies on a bed of sharp nails without harm because

her weight is distributed over hundreds of nails.

As two objects moving toward each other due to gravity get closer, the acceleration of each

increases

When the distance between two stars decreases by one-third, the force between them

increases to nine times as much.

When a twirling ice skater brings her arms inward, her rotational speed

increases.

Compared to the density of a kilogram of feathers, the density of a kilogram of lead is

more

An industrial flywheel has a greater rotational inertia when most of its mass is

nearer the rim

The buoyant force on an object is least when the object is

partly submerged.