Question 1

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?

Accepted Answer

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

Question 2

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. )

Accepted Answer

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 
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 3

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?

Accepted Answer

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

Question 4

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

Accepted Answer

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

Question 5

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)

Accepted Answer

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 
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 6

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?

Accepted Answer

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

Question 7

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. )

Accepted Answer

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 
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 8

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?

Accepted Answer

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 
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 9

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?

Accepted Answer

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

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?

Accepted Answer

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

Question 11

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. )

Accepted Answer

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

Question 12

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?

Accepted Answer

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. 
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 13

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. )

Accepted Answer

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

Question 14

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

Accepted Answer

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

Question 15

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?

Accepted Answer

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

Question 16

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

Accepted Answer

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

Question 17

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)

Accepted Answer

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 
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 18

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

Accepted Answer

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

Exam 9: Solids and Fluids

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?

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. )

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?

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

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 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?

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. )

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?

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 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?

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 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. )

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

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?

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

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)

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

Introduction

Introduction: Part A

Motion in One Dimension

Motion in One Dimension: Part A

Vectors and Two-Dimensional Motion

Vectors and Two-Dimensional Motion: Part A

The Laws of Motion

The Laws of Motion: Part A

Energy

Energy: Part A

Momentum and Collisions

Momentum and Collisions: Part A

Rotational Motion and the Law of Gravity

Rotational Motion and the Law of Gravity: Part A

Rotational Equilibrium and Rotational Dynamics

Rotational Equilibrium and Rotational Dynamics: Part A

Solids and Fluids: Part A

Thermal Physics

Thermal Physics: Part A

Energy in Thermal Processes Heat and Internal Energy

Energy in Thermal Processes Heat and Internal Energy: Part A

The Laws of Thermodynamics Work in Thermodynamic Processes

The Laws of Thermodynamics Work in Thermodynamic Processes: Part A

Vibrations and Waves

Vibrations and Waves: Part A

Sound

Sound: Part A

Electric Forces and Electric Fields

Electric Forces and Electric Fields: Part A

Electrical Energy and Capacitance

Electrical Energy and Capacitance: Part A

Current and Resistance Electric Current

Current and Resistance Electric Current: Part A

Direct-Current Circuits Sources of EMF

Direct-Current Circuits Sources of EMF: Part A

Magnetism Magnets

Magnetism Magnets: Part A

Induced Voltages and Inductance

Induced Voltages and Inductance: Part A

Alternating-Current Circuits and Electromagnetic Waves

Alternating-Current Circuits and Electromagnetic Waves: Part A

Reflection and Refraction of Light

Reflection and Refraction of Light: Part A

Mirrors and Lenses

Mirrors and Lenses: Part A

Wave Optics

Wave Optics: Part A

Optical Instruments

Optical Instruments: Part A

Relativity

Relativity: Part A

Quantum Physics Blackbody Radiation and Plancks Hypothesis

Quantum Physics Blackbody Radiation and Plancks Hypothesis: Part A

Atomic Physics

Atomic Physics: Part A

Nuclear Physics

Nuclear Physics: Part A

Nuclear Energy and Elementary Particles

Nuclear Energy and Elementary Particles: Part A

Particle Collisions, Mediating Photons, and Quark Structures: Exploring the Fundamentals of Physics

Filters

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. )

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 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?

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. )

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 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. )

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

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)