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Prepare for the review game.

In order to calculate pressure exerted on a surface, what quantity is divided by the surface area

force

What is the SI unit of pressure? the pascal

A pressure of 70 N/m2 equals 70 Pa.

Which of the following materials is NOT a fluid?› air› gasoline› cork› Water

Cork

If the air inside a balloon exerts a force of 1.5 N on an area of 0.5 m2, what is the pressure inside the balloon?

3 N/m2

Atmospheric pressure is caused by the weight of the atmosphere above a

particular location.

The pressure of air at sea level is approximately

101 kPa.

According to Bernoulli’s principle, is the fertilizer solution in Figure 13-2 pulled or pushed up the tube (B)?

The solution is pushed up the tube because of the pressure difference

Which principle states that a change in the pressure at any point in a fluid in a closed container is transmitted equally and unchanged in all directions throughout the fluid?

Pascal’s principle

Where is fluid pressure greatest?› A.30 centimeters below the surface of a

swimming pool› B.1 meter below the surface of a swimming

pool› C.2 meters below the surface of a swimming

pool› D.The pressure is the same in all parts of a

swimming pool. 2 meters below the surface of a swimming

pool

The operation of a hydraulic lift system is explained by

Pascal’s principle.

Where will the greatest increase in pressure occur if you squeeze the middle of an upright, closed soft-drink bottle?

The pressure will increase equally everywhere within the bottle.

The hydraulic system of a dump truck is designed to multiply

force.

State Bernoulli’s principle. As the speed of a fluid increases, the

pressure within the fluid decreases.

A cork is floating in salty water. As more salt is added to the water to increase its density, the cork will

Float at a higher level

The upward force acting on the wing of an airplane in flight is called

lift

Which of the following statements is true about an airplane wing during flight?› A.Air above the wing travels faster than air

below the wing.› B.Air below the wing travels faster than air

above the wing.› C.The wing exerts pressure equally in all

directions.› D.The lift acting on the wing reduces the

weight of the wing. A

The upward force acting on an object submerged in a fluid is called

Buoyant force

The SI unit of pressure is the Pascal

The strength of the buoyant force acting on an object in a fluid depends on the object’s

volume.

A ball is floating partially submerged in a liquid. The buoyant force acting on the ball equals the

volume of the ball below the surface.

Which of the following substances will float in corn syrup? (The density of corn syrup is 1.38 g/cm3.)› copper (8.9 g/cm3)› iron (7.8 g/cm3)› silver (10.5 g/cm3)› glycerin (1.26 g/cm3)

glycerin (1.26 g/cm3)

The buoyant force on an object in a fluid is equal to the weight of the

fluid displaced by the object.

The formula Force/Area is used to calculate

Pressure

Two identical corks float in separate beakers. One beaker contains distilled water. The other contains very salty water. Which of the following statements is true?› A.The corks float at the same level in both liquids.› B.The cork in the very salty water floats at a lower

level than the other cork.› C.The corks will eventually sink.› D.Both corks are subject to the same buoyant

force. D.Both corks are subject to the same buoyant

force.

In this picture, spheres of which color have the greatest density?

Black

A substance that flows and assumes the shape of its container is a(an)

Fluid

Why does a hot-air balloon float?› A.The shape of the balloon provides lift.› B.The volume of the air displaced by the

balloon is less than the volume of the balloon.› C.The weight of the air displaced is less than

the volume of the balloon.› D.The weight of the balloon is less than the

weight of the air displaced by the balloon. D.The weight of the balloon is less than

the weight of the air displaced by the balloon.

The pressure exerted by a fluid at any given depth is exerted ____________________ in all directions.

Equally

As your altitude increases, air pressure Decreases

A hydraulic jack is an application of ____________________ principle.

Pascal’s

A device that uses pressurized fluids acting on pistons of different sizes to change a force is called a(an)

Hydraulic system

Even a rock at the bottom of a lake has a(an) ____________________ force acting upward on it.

Buoyant  

As the speed of a fluid increases, the ____________________ within the fluid decreases.

Pressure

In a hydraulic lift system, the fluid pressure exerted throughout the system is

Constant

The downward force produced when air flows over the winglike spoiler on a race car is an example of ____________________ principle.

Bernoulli’s

The direction of the buoyant force on an object placed in a fluid is

Upward

The unit g/cm3 is often used to express Density

As you climb a high mountain, the buoyant force exerted on you by the atmosphere

Decreases

A submerged submarine alters its ____________________ to rise or fall in the water.

Density

Which exerts greater pressure on the floor—standing flat-footed or standing on tiptoes

Standing on tiptoes

The apparent loss of weight of an object in a fluid is called

Buoyancy

How do the particles of a liquid exert pressure on a container?

The hit the container

In this picture, on how many spheres is the buoyant force less than the weight of the sphere?

Four

Why aren’t organisms that live on the seafloor crushed by water pressure?

The pressure inside its body is balanced with the pressure outside its body

The relationship between buoyant force and weight of a displaced fluid was first stated by

Archimedes.

A ball of clay sinks when placed in water. The same piece of clay floats if it is made into the shape of a boat. Compare the volume of water displaced by the ball with the volume displaced by the boat shape.

The boat shape displaces a larger volume of water

How are density and buoyancy related? When an object is less dense than the

fluid it is in, the buoyant force will allow the object to float. If the object is more dense the buoyant force will not be great enough and the object will sink.