Deck 9: Solids and Fluids

Question 1

How large a force is necessary to stretch a 1-mm-diameter steel wire (Y = 2.0 × 10¹¹ N/m²)by 8.0%?

A) 19.0 × 10³ N
B) 12.6 × 10³ N
C) 12.3 × 10³ N
D) 25.1 × 10⁴ N
E) ​12.6 × 10⁴ N

Answer 1

12.6 × 10³ N

Question 2

Consider two steel rods,A and B.B has three times the area and twice the length of A,so Young's modulus for B will be what factor times Young's modulus for A?

A) 3.0
B) 0.5
C) 1.5
D) 1.0

Answer 2

1.0

Question 3

A tire stops a car by use of friction.What modulus should we use to calculate the stress and strain on the tire?

A) Young's modulus
B) compression modulus
C) shear modulus
D) bulk modulus

Answer 3

shear modulus

Question 4

What is the total mass of the Earth's atmosphere? (The radius of the Earth is 6.4 × 10⁶ m,and atmospheric pressure at the surface is 10⁵ N/m². )

A) 5 × 10¹⁶ kg
B) 1 × 10¹⁸ kg
C) 5 × 10¹⁸ kg
D) 1 × 10²⁰ kg

Question 5

A solid object is made of two materials,one material having density of 2 000 kg/m³ and the other having density of 5 500 kg/m³.If the object contains equal masses of the materials,what is its average density?

A) 2 933 kg/m³
B) 3 750 kg/m³
C) 3 933 kg/m³
D) 7 500 kg/m³
E) more information is needed​

Question 6

The Greenland ice sheet can be one km thick.Estimate the pressure underneath the ice.(The density of ice is 918 kg/m³. )

A) 9.0 × 10⁵ Pa (9 atm)
B) 2.5 × 10⁶ Pa (25 atm)
C) 4.5 × 10⁶ Pa (45 atm)
D) 9.0 × 10⁶ Pa (90 atm)

Question 7

Bar One has a Young's modulus that is bigger than that of Bar Two.This indicates Bar One:

A) is longer than Bar Two.
B) has a greater cross-sectional area than Bar Two.
C) has a greater elastic limit than Bar Two.
D) is made of material that is different from Bar Two.

Question 8

In an elastic solid there is a direct proportionality between strain and:

A) elastic modulus.
B) temperature.
C) cross-sectional area.
D) stress.

Question 9

The quantity "stress" expressed in terms of the fundamental quantities (mass,length,time)is equivalent to:

A) MLT−¹.
B) ML−¹T−².
C) M²L−¹T−³.
D) a dimensionless quantity.

Question 10

The standard kilogram is a platinum-iridium cylinder 30.0 mm in height and 31.0 mm in diameter.What is the density of the material?

A) 44.2 g/cm³
B) 43.3 g/cm³
C) 45.1 g/cm³
D) 10.0 g/cm³
E) 86.5 g/cm³

Question 11

A copper wire of length 5.0 m,cross sectional area 7.5 × 10−⁶ m² and Young's modulus 11 × 10¹⁰ N/m² has a 190-kg load hung on it.What is its increase in length? (g = 9.8 m/s²)

A) 0.50 mm
B) 11.7 mm
C) 10.9 mm
D) 11.3 mm
E) ​22.6 mm

Question 12

The pressure inside a commercial airliner is maintained at 1.00 atm (10⁵ Pa).What is the net outward force exerted on a 1.0 m × 2.0 m cabin door if the outside pressure is 0.30 atm?

A) 140 N
B) 1 400 N
C) 14 000 N
D) 140 000 N

Question 13

The bulk modulus of a material,as a meaningful physical property,is applicable to which of the following?

A) only solids
B) only liquids
C) only gases
D) solids,liquids and gases

Question 14

Which state of matter is associated with the very highest of temperatures?

A) liquid
B) plasma
C) gas
D) solid

Question 15

The quantity "pressure" expressed in terms of the fundamental quantities (mass,length,time)is equivalent to:

A) MLT−¹.
B) ML−¹T−².
C) M²L−¹T−³.
D) a dimensionless quantity.

Question 16

A solid object is made of two materials,one material having density of 2 000 kg/m³ and the other having density of 5 000 kg/m³.If the object contains equal volumes of the materials,what is its average density?

A) 2 857 kg/m³
B) 3 500 kg/m³
C) 4 500 kg/m³
D) 7 000 kg/m³
E) ​more information is needed

Question 17

The quantity "strain" expressed in terms of the fundamental quantities (mass,length,time)is equivalent to:

A) MLT−¹.
B) ML−¹T−².
C) M²L−¹T−³.
D) a dimensionless quantity.

Question 18

A stonecutter's chisel has an edge area of 0.45 cm².If the chisel is struck with a force of 48 N,what is the pressure exerted on the stone?

A) 1 067 Pa
B) 10 670 Pa
C) 106 700 Pa
D) 1 067 000 Pa
E) ​533 500 Pa

Question 19

When water freezes,it expands about nine percent.What would be the pressure increase inside your automobile engine block if the water in there froze? (The bulk modulus of ice is 2.0 × 10⁹ Pa,and 1 atm = 1.0 × 10⁵ Pa. )

A) 18 atm
B) 270 atm
C) 1 080 atm
D) 1 800 atm

Question 20

A uniform pressure of 6.9 × 10⁵ N/m² is applied to all six sides of a copper cube.What is the percentage change in volume of the cube? (for copper,B = 14 × 10¹⁰ N/m²)

A) 1.2 × 10−² %
B) 0.9 × 10−² %
C) 2.0 × 10−² %
D) 0.5 × 10−³ %
E) ​0.0 × 10−³ %

Question 21

A large stone is resting on the bottom of the swimming pool.The normal force of the bottom of the pool on the stone is equal to the:

A) weight of the stone.
B) weight of the water displaced.
C) sum of the weight of the stone and the weight of the displaced water.
D) difference between the weight of the stone and the weight of the displaced water.

Question 22

What volume of water is displaced by a submerged 2.5-kg cylinder made of solid aluminum? (aluminum density = 2.7 × 10³ kg/m³ and water density = 1.0 × 10³ kg/m³)

A) 9.3 × 10−⁴ m³
B) 0.7 × 10³ m³
C) 0.9 × 10³ m³
D) 92.6 × 10−⁴ m³
E) ​8.3 × 10³ m³

Question 23

If the column of mercury in a barometer stands at 73.8 cm,what is the atmospheric pressure? (The density of mercury is 13.6 × 10³ kg/m³ and g = 9.80 m/s²)

A) 0.984 × 10⁵ N/m²
B) 98.361 × 10⁵ N/m²
C) 1.184 × 10⁵ N/m²
D) 0.018 × 10⁵ N/m²
E) ​1.024 × 10⁵ N/m²

Question 24

What is the total force on the bottom of a 4.0-m-diameter by 1.5-m-deep round wading pool due to the weight of the air and the weight of the water? (Note the pressure contribution from the atmosphere is 1.0 × 10⁵ N/m²,the density of water is 1 000 kg/m³,and g = 9.8 m/s². )

A) 14.4 × 10⁵ N
B) 57.7 × 10⁶ N
C) 2.5 × 10⁶ N
D) 15.9 × 10⁶ N
E) ​12.9 × 10⁵ N

Question 25

A ping-pong ball has an average density of 0.0840 g/cm³ and a diameter of 3.80 cm.What force would be required to keep the ball completely submerged under water?

A) 1.000 N
B) 0.788 N
C) 0.516 N
D) 0.258 N

Question 26

How deep under the surface of a lake would the pressure be double that at the surface? (1 atm = 1.01 × 10⁵ Pa)

A) 1.00 m
B) 9.80 m
C) 10.3 m
D) 32.2 m

Question 27

A cube of wood of density 0.78 g/cm³ is 11 cm on a side.When placed in water,what height of the block will float above the surface? (water density = 1.00 g/cm³)

A) 8.6 cm
B) 11 cm
C) 2.4 cm
D) 3.4 cm
E) ​1.4 cm

Question 28

A solid rock,suspended in air by a spring scale,has a measured mass of 8.50 kg.When the rock is submerged in water,the scale reads 3.50 kg.What is the density of the rock? (water density = 1 000 kg/m³)

A) 0.71 × 10³ kg/m³
B) 0.7 × 10³ kg/m³
C) 0.29 × 10³ kg/m³
D) 1.7 × 10³ kg/m³
E) ​2.2 × 10³ kg/m³

Question 29

The bottom of a flat-bottomed aluminum boat has area = 4.2 m² and mass = 60 kg.If two fishermen and their fishing gear with total mass of 315 kg are placed in the boat,how much lower will the boat ride in the water? (H₂O density = 1.0 × 10³ kg/m³)

A) 0.014 m
B) 0.061 m
C) 0.075 m
D) 0.089 m
E) ​1.323 m

Question 30

Dams at two different locations are needed to form a lake.When the lake is filled,the water level will be at the top of both dams.The Dam #2 is twice as high and twice as wide as Dam #1.How much greater is the force of the water on Dam #2 than the force on Dam #1? (Ignore atmospheric pressure;it is pushing on both sides of the dams. )

A) 2
B) 4
C) 8
D) 16

Question 31

The water behind Grand Coulee Dam is 1 100 m wide and 150 m deep.Find the hydrostatic force on the back of the dam.(Hint: the total force = average pressure × area)

A) 24.26 × 10⁹ N
B) 15.13 × 10¹⁰ N
C) 12.13 × 10¹⁰ N
D) 9.13 × 10¹⁰ N
E) ​0.09 × 10¹⁰ N

Question 32

Atmospheric pressure is 1.0 × 10⁵ N/m²,and the density of air is 1.29 kg/m³.If the density of air is constant as you get higher and higher,calculate the height of the atmosphere needed to produce this pressure.

A) 7 900 m
B) 77 000 m
C) 1 260 m
D) 10 300 m

Question 33

Legend says that Archimedes,in determining whether or not the king's crown was made of pure gold,measured its volume by the water displacement method.If the density of gold is 19.3 g/cm³,and the crown's mass is 600 g,what volume would be necessary to prove that it is pure gold?

A) 31.1 cm³
B) 0.03 × 10³ cm³
C) 32.1 × 10³ cm³
D) 30.1 × 10−² cm³
E) ​11 580 cm³

Question 34

By what factor is the total pressure greater at a depth of 810 m in water than at the surface where pressure is one atmosphere? (water density = 1.0 × 10³ kg/m³,1 atmosphere pressure = 1.01 × 10⁵ N/m²,and g = 9.8 m/s²)

A) 8
B) 79
C) 89
D) 69
E) ​7 938

Question 35

The bottom of a flat-bottomed aluminum boat has an area of 4.4 m² and the boat's mass is 62 kg.When set afloat in water,how far below the water surface is the boat bottom? (water density = 1.0 × 10³ kg/m³)

A) 14 m
B) 0.014 m
C) 0.114 m
D) 0.273 m
E) ​0.024 m

Question 36

A heavily loaded boat is floating in a pond.The boat sinks because of a leak.What happens to the surface level of the pond?

A) It stays the same.
B) It goes up.
C) It goes down.
D) More information is needed to reach a conclusion.

Question 37

As ice floats in water,about 10% of the ice floats above the surface of the water.If we float some ice in a glass of water,what will happen to the water level as the ice melts?

A) The water level will rise 10% of the volume of the ice that melts.
B) The water level will rise,but not as much as the 10% indicated in answer
C) The water level will remain unchanged.
D) The water level will become lower.

Question 38

A 13 500-N car on a hydraulic lift rests on a cylinder with a piston of radius 0.10 m.If a connecting cylinder with a piston of 0.050-m radius is driven by compressed air,what force must be applied to this smaller piston in order to lift the car?

A) 3 375 N
B) 54 N
C) 3 875 N
D) 3 275 N
E) ​13 500 N

Question 39

In a large tank of liquid,the hydrostatic pressure at a given depth is a function of:

A) depth.
B) surface area.
C) liquid density.
D) Choices a and c are both valid.

Question 40

A blimp is filled with 430 m³ of helium.How big a payload can the balloon lift? (The density of air is 1.29 kg/m³;the density of helium is 0.18 kg/m³. )

A) 387 kg
B) 555 kg
C) 77 kg
D) 477 kg
E) ​632 kg

Question 41

A block of wood has specific gravity 0.79.When placed in water,what percent of the volume of the wood is above the surface?

A) 0,the block sinks.
B) 21%
C) 79%
D) 50%
E) ​100%

Question 42

A Boeing-737 airliner has a mass of 20 500 kg.The total area of the wings is 100 m².What must be the pressure difference between the top and bottom of the wings to keep the airplane up?

A) 2 009 Pa
B) 21 Pa
C) 205 Pa
D) 2 019 Pa
E) ​1 909 Pa

Question 43

An ideal fluid,of density 0.90 × 10³ kg/m³,flows at 5.0 m/s through a level pipe with radius of 0.5 cm.The pressure in the fluid is 1.3 × 10⁵ N/m².This pipe connects to a second level pipe,with radius of 1.4 cm.Find the speed of flow in the second pipe.

A) 39.2 m/s
B) 1.79 m/s
C) 0.64 m/s
D) 14 m/s
E) ​5.13 m/s

Question 44

Air pressure is 1.0 × 10⁵ N/m²,air density is 1.3 kg/m³,and the density of soft drinks is 1.0 × 10³ kg/m³.If one blows carefully across the top of a straw sticking up 0.130 m from the liquid in a soft drink can,it is possible to make the soft drink rise half way up the straw and stay there.How fast must the air be blown across the top of the straw?

A) 0.04 m/s
B) 31 m/s
C) 1.6 m/s
D) 22 m/s​
E) ​980 m/s

Question 45

How much air must be pushed downward at 40.0 m/s to keep an 800-kg helicopter aloft?

A) 20 kg/s
B) 196 kg/s
C) 32 000 kg/s
D) 201 kg/s
E) ​186 kg/s

Question 46

An ideal fluid flows through a pipe made of two sections with diameters of 1.0 and 4.0 inches,respectively.The speed of the fluid flow through the 4.0-inch section will be what factor times that through the 1.0-inch section?

A) 16
B) 8
C) 15
D)

E) ​

Question 47

Water (density = 1 × 10³ kg/m³)flows at 11 m/s through a pipe with radius 0.025 m.The pipe goes up to the second floor of the building,2.5 m higher,and the pressure remains unchanged.What is the radius of the pipe on the second floor?

A) 0.01 m
B) 0.028 m
C) 0.001 m
D) 0.18 m
E) ​0.023 m

Question 48

The Garfield Thomas water tunnel at Pennsylvania State University has a circular cross-section that constricts from a diameter of 3.6 m to the test section,which is 1.2 m in diameter.If the speed of flow is 3.5 m/s in the large-diameter pipe,determine the speed of flow in the test section.

A) 0.4 m/s
B) 3.5 m/s
C) 32 m/s
D) 4 m/s
E) ​34 m/s

Question 49

A Venturi tube may be used as the inlet to an automobile carburetor.If the inlet pipe of 2.0 cm diameter narrows to 1.0 cm diameter,what is the pressure drop in the constricted section for airflow of 2.5 m/s in the 2-cm section? (Assume air density is 1.25 kg/m³. )

A) 16 Pa
B) 59 Pa
C) 61 Pa
D) 23 Pa
E) ​117 Pa

Question 50

Think of Bernoulli's equation as it pertains to an ideal fluid flowing through a horizontal pipe.Imagine that you take measurements along the pipe in the direction of fluid flow.What happens to the sum of the pressure and energy per unit volume?

A) It increases as the pipe diameter increases.
B) It decreases as the pipe diameter increases.
C) It remains constant as the pipe diameter increases.
D) No choices above are valid.

Question 51

Water (density = 1 × 10³ kg/m³)flows at 15 m/s through a pipe with radius 0.040 m.The pipe goes up to the second floor of the building,3.0 m higher,and the pressure remains unchanged.What is the speed of the water flow in the pipe on the second floor?

A) 13 m/s
B) 17 m/s
C) 166 m/s
D) 14 m/s
E) ​6 m/s

Question 52

A hole is poked through the metal side of a drum holding water.The hole is 18 cm below the water surface.What is the initial speed of outflow?

A) 1.9 m/s
B) 18.8 m/s
C) 0.6 m/s
D) 3.5 m/s
E) ​1.3 m/s

Question 53

Water pressurized to 3 × 10⁵ Pa is flowing at 5.0 m/s in a pipe which contracts to 1/2 of its former area.What are the pressure and speed of the water after the contraction? (Density of water = 1 × 10³ kg/m³. )

A) 2.6 × 10⁵ Pa,10 m/s
B) 3 × 10⁵ Pa,2.5 m/s
C) 3 × 10⁵ Pa,10 m/s
D) 4.6 × 10⁵ Pa,10 m/s
E) ​2.6 × 10⁵ Pa,2.5 m/s

Question 54

Water comes down the spillway of a dam from an initial vertical height of 165 m.What is the highest possible speed of the water at the end of the spillway?

A) 6 m/s
B) 18 m/s
C) 57 m/s
D) 1 617 m/s
E) ​3 234 m/s

Question 55

A jet of water flowing from a hose at 14 m/s is directed against a wall.If the mass flow in the fluid stream is 3.0 kg/s,what force is the water applying to the wall if backsplash is negligible?

A) 42 N
B) 0.2 N
C) 44 N
D) 411.6 N
E) ​40 N

Question 56

The flow rate of a liquid through a 4.0-cm-radius pipe is 0.0070 m³/s.The average fluid speed in the pipe is:

A) 0.04 m/s.
B) 0.005 m/s.
C) 0.14 m/s.
D) 1.4 m/s.
E) ​14 m/s.

Question 57

An ideal fluid,of density 0.85 × 10³ kg/m³,flows at 0.28 kg/s through a pipe of radius 0.017 m.What is the fluid speed?

A) 3.34 m/s
B) 0.0031 m/s
C) 308.4 m/s
D) 0.36 m/s​
E) ​1.3 m/s

Question 58

A heavily loaded boat is floating in a pond.The boat starts to sink because of a leak but quick action plugging the leak stops the boat from going under although it is now deeper in the water.What happens to the surface level of the pond?

A) It stays the same.
B) It goes up.
C) It goes down.
D) More information is needed to reach a conclusion.

Question 59

The flow rate of blood through the average human aorta,of radius 1.0 cm,is about 90 cm³/s.What is the speed of the blood flow through the aorta?

A) 14 cm/s
B) 32 cm/s
C) 37 cm/s
D) 29 cm/s

Question 60

A fountain sends water to a height of 100 m.What must be the pressurization (above atmospheric)of the underground water system? (1 atm = 10⁵ N/m²)

A) 1 atm
B) 44.3 atm
C) 10.8 atm
D) 9.8 atm
E) ​0.1 atm

Question 61

In order to overcome a surface tension of a fluid,a force of 1.34 × 10−² N is required to lift a wire ring of circumference 12.0 cm.What is the surface tension of the fluid?

A) 0.056 N/m
B) 0.112 N/m
C) 0.556 N/m
D) 5.583 N/m
E) ​16.08 N/m

Question 62

The condition for onset of turbulent flow is that the Reynolds Number reaches what value?

A) 1 000
B) 2 000
C) 3 000
D) 4 000

Question 63

A container is filled with water and the pressure at the container bottom is P.If the container is instead filled with oil having specific gravity 0.80,what new bottom pressure results?

A) a pressure < P
B) the same pressure P
C) a pressure > P
D) This is unable to be determined with the information given.

Question 64

Which of the following characterizes the net force on a particle falling through a fluid at its terminal speed?

A) It is at a maximum.
B) It is upwards.
C) It is downwards.
D) It is zero.

Question 65

A fluid has a density of 1 040 kg/m³.If it rises to a height of 1.6 cm in a 1.5-mm diameter capillary tube,what is the surface tension of the liquid? Assume a contact angle of zero.

A) 0.061 N/m
B) 0.122 N/m
C) 6.115 N/m
D) 0.245 N/m
E) ​12.23 N/m

Question 66

Water is sent from a fire hose at 35 m/s at an angle of 30° above the horizontal.What is the maximum height reached by the water?

A) 8 m
B) 16 m
C) 31 m
D) 306 m
E) ​62 m

Question 67

How much power is theoretically available from a mass flow of 1 200 kg/s of water that falls a vertical distance of 110 m?

A) 1 294 kW
B) 132 kW
C) 129 W
D) 1 299 W
E) ​1 294 W

Question 68

Spherical particles of density 1.6 g/cm³ are shaken in a container of water (viscosity = 1.0 × 10−³ N⋅s/m³).The water is 10.0 cm deep and is allowed to stand for 35 minutes.What is the radius of the largest particles still in suspension at that time?
​

A) 6 × 10−⁶ m
B) 7.3 × 10−⁶ m
C) 2.8 × 10−⁶ m
D) 2 × 10−⁶ m
E) ​4.7 × 10−⁶ m

Question 69

Spherical particles of density 2.0 g/cm³ are shaken in a container of water (viscosity = 1.0 × 10−³ N⋅s/m³).The water is 7.0 cm deep and is allowed to stand for 30 minutes.What is the greatest terminal velocity of the particles still in suspension at that time?
​

A) 2 × 10−⁵ m/s
B) 2.9 × 10−⁵ m/s
C) 4.9 × 10−⁵ m/s
D) 3.9 × 10−⁵ m/s
E) ​5.5 × 10−⁵ m/s

Question 70

An ice cube with a small solid steel sphere frozen inside floats in a glass of water filled to the brim.What happens to the level of water in the glass as a result of the ice melting?

A) It goes up,overflowing.
B) It stays the same.
C) It goes down.
D) It depends on air pressure,thus the answer is indeterminate.

Question 71

At a pressure of 1 atmosphere a column of mercury in a barometer is supported to the height h = 0.76 m.The density of mercury is 13.6 × 10³ kg/m³.A barometer of similar design filled with water would support a column of water how high at a pressure of 1 atmosphere?

A) more than ten times h
B) about 1.36 h
C) less than one tenth h
D) the same height h

Question 72

Water is being sprayed from a nozzle at the end of a garden hose of diameter 2.0 cm.If the nozzle has an opening of diameter 1.0 cm,and if the water leaves the nozzle at a speed of 12 m/s,what is the speed of the water inside the hose?

A) 3 m/s
B) 48 m/s
C) 0.02 m/s
D) 4 m/s
E) ​also 12 m/s

Question 73

It takes 2.5 minutes to fill a gas tank with 50 liters of gasoline.If the pump nozzle is 2.0 cm in radius,what is the average speed of the gasoline as it leaves the nozzle? (1 000 liters = one cubic meter)

A) 2.7 m/s
B) 0.3 m/s
C) 15.9 m/s
D) 1.3 m/s
E) ​20 m/s

Question 74

A centrifuge rotates at 100 rev/s (i.e. ,628 rad/s).If the test tube places the suspension at 8.0 cm from the axis of rotation,by what factor are the terminal speeds of the settling particles increased as compared to sedimentation cause by gravity?

A) 3.2 × 10³
B) 321.9
C) 31.6
D) 5 × 10⁵
E) ​4.2 × 10³

Question 75

A container is filled with water and the pressure at the bottom of the container is P.Then the container is emptied halfway and topped off with oil of density 0.8 × 10³ kg/m³,which floats on top of the water.What is the pressure at the bottom of the container now?

A) a pressure < P
B) the same pressure P
C) a pressure > P
D) This is unable to be determined with the information given.
E) ​a pressure < 0.5P

Question 76

A pipe carrying water has a radius of 1.0 cm.If the flow velocity is 9.0 cm/s,which of the following characterizes the flow? Take the viscosity of water to be 1.0 × 10−³ N⋅s/m.

A) streamlined
B) unstable
C) turbulent
D) stagnant

Question 77

When an artery gets a constricted region due to plaque,how does the pressure in this region compare to the pressure in an unconstricted region adjacent?

A) Since this is a closed system,the pressure is the same in both regions.
B) In the constricted region the blood moves at a higher speed than in the unconstricted region resulting in an increased pressure.
C) In the constricted region the blood moves at a higher speed than in the unconstricted region resulting in a decreased pressure.
D) In the constricted region the blood moves at a lower speed than in the unconstricted region resulting in an increased pressure.

Question 78

A pipe of diameter four cm is replaced by one of the same length but of diameter twelve cm.If the pressure difference between the ends of the pipe remains the same,by what factor is the rate of flow of a viscous liquid through it changed?
​

A) 3
B) 9
C) 27
D) 81
E) ​243