Question 1

Water flows over a section of Niagara Falls at a rate of 1.20 × 106 kg/s and falls 51.0 m.What is the power dissipated by the waterfall?

Accepted Answer

A)  599.76 MW 
B)  61.2 MW 
C)  43 MW 
D)  499.76 MW 
E)  ​699.76 MW 
A)  599.76 MW 
B)  61.2 MW 
C)  43 MW 
D)  499.76 MW 
E)  ​699.76 MW

Question 2

If during a given physical process the only force acting on an object is friction,which of the following must be assumed in regard to the object's kinetic energy?

Accepted Answer

A)  It decreases. 
B)  It increases. 
C)  It remains constant. 
D)  It cannot be determined from the information given. 
A)  It decreases. 
B)  It increases. 
C)  It remains constant. 
D)  It cannot be determined from the information given.

Question 3

A speed boat requires 82 kW to move at a constant speed of 16 m/s.What is the resistive force of the water at this speed?

Accepted Answer

A)  1 310 N 
B)  5 130 N 
C)  5 230 N 
D)  5 030 N 
E)  ​1 410 N 
A)  1 310 N 
B)  5 130 N 
C)  5 230 N 
D)  5 030 N 
E)  ​1 410 N

Question 4

Rupel pushes a box 3.00 m by applying a 19.0-N horizontal force.What work does she do?

Accepted Answer

A)  6.33 J 
B)  0.16 J 
C)  57 J 
D)  -57 J 
E)  ​19 J 
A)  6.33 J 
B)  0.16 J 
C)  57 J 
D)  -57 J 
E)  ​19 J

Question 5

A simple pendulum,3.0 m in length,is released with a push when the support string is at an angle of 20° from the vertical.If the initial speed of the suspended mass is 1.3 m/s when at the release point,what is its speed at the bottom of the swing? (g = 9.8 m/s2)

Accepted Answer

A)  2.3 m/s 
B)  1.9 m/s 
C)  6.4 m/s 
D)  5.2 m/s 
E)  ​7.8 m/s 
A)  2.3 m/s 
B)  1.9 m/s 
C)  6.4 m/s 
D)  5.2 m/s 
E)  ​7.8 m/s

Question 6

A 180-hp engine can deliver,in SI units,an average power of ____.(1 hp = 746 W)

Accepted Answer

A)  0.24 W 
B)  4.14 W 
C)  134 300 W 
D)  180 W 
E)  ​926 W 
A)  0.24 W 
B)  4.14 W 
C)  134 300 W 
D)  180 W 
E)  ​926 W

Question 7

A Hooke's law spring is compressed a distance d and is used to launch a mass m vertically to a height h above its starting position.Under the same compression d,the spring is now used to launch a mass of 2m.How high does this second mass rise?

Accepted Answer

A)  h 
B)  h/2 
C)  h/1.41 
D)  h/4 
A)  h 
B)  h/2 
C)  h/1.41 
D)  h/4

Question 8

The rate at which work is done is equivalent to which of the following?

Accepted Answer

A)  increase in potential energy 
B)  thermal energy 
C)  potential energy 
D)  power 
A)  increase in potential energy 
B)  thermal energy 
C)  potential energy 
D)  power

Question 9

A student has to work the following problem: A block is being pulled along at constant speed on a horizontal surface a distance d by a rope supplying a force F at an angle of elevation q.The surface has a frictional force acting during this motion.How much work was done by friction during this motion? The student calculates the value to be -Fdsinq.How does this value compare to the correct value?

Accepted Answer

A)  It is the correct value. 
B)  It is too high. 
C)  It is too low. 
D)  The answer cannot be found until it is known whether q is greater than,less than,or equal to 45°. 
A)  It is the correct value. 
B)  It is too high. 
C)  It is too low. 
D)  The answer cannot be found until it is known whether q is greater than,less than,or equal to 45°.

Question 10

A professional skier reaches a speed of 55 m/s on a 30° ski slope.Ignoring friction,what was the minimum distance along the slope the skier would have had to travel,starting from rest?
​

Accepted Answer

A)  154.34 m 
B)  178.22 m 
C)  308.67 m 
D)  5.61 m 
E)  ​0.003 m 
A)  154.34 m 
B)  178.22 m 
C)  308.67 m 
D)  5.61 m 
E)  ​0.003 m

Question 11

If both mass and velocity of a ball are tripled,the kinetic energy is increased by a factor of:

Accepted Answer

A)  3. 
B)  6. 
C)  9. 
D)  27. 
A)  3. 
B)  6. 
C)  9. 
D)  27.

Question 12

A horizontal force of 81 N is applied to move a 47-kg cart across a 7.0-m level surface.What work is done by the 81-N force?

Accepted Answer

A)  12.06 J 
B)  26649 J 
C)  567 J 
D)  543.86 J 
E)  ​0.25 J 
A)  12.06 J 
B)  26649 J 
C)  567 J 
D)  543.86 J 
E)  ​0.25 J

Question 13

A girl and her bicycle have a total mass of 43.0 kg.At the top of the hill her speed is 5.0 m/s,and her speed doubles as she rides down the hill.The hill is 15.0 m high and 100 m long.How much kinetic energy and potential energy is lost to friction?

Accepted Answer

A)  4,709 J 
B)  6,859 J 
C)  4,171 J 
D)  4,809 J 
E)  ​4,609 J 
A)  4,709 J 
B)  6,859 J 
C)  4,171 J 
D)  4,809 J 
E)  ​4,609 J

Question 14

The net force acting on a 4.0-kg object is given by Fx = (10 − x)N,where Fx is in newtons and x is in meters.How much work is done on the object as it moves from x = 0 to x = 15 m?

Accepted Answer

A)  5 J 
B)  15 J 
C)  37.5 J 
D)  18.75 J 
E)  ​28.125 J 
A)  5 J 
B)  15 J 
C)  37.5 J 
D)  18.75 J 
E)  ​28.125 J

Question 15

Two blocks are released from the top of a building.One falls straight down while the other slides down a smooth ramp.If all friction is ignored,which one is moving faster when it reaches the bottom?

Accepted Answer

A)  The block that went straight down. 
B)  The block that went down the ramp. 
C)  They both will have the same speed. 
D)  Insufficient information to work the problem. 
A)  The block that went straight down. 
B)  The block that went down the ramp. 
C)  They both will have the same speed. 
D)  Insufficient information to work the problem.

Question 16

A baseball catcher puts on an exhibition by catching a 0.10-kg ball dropped from a helicopter at a height of 81 m.What is the speed of the ball just before it hits the catcher's glove 1 m above the ground? (g = 9.8 m/s2 and ignore air resistance)

Accepted Answer

A)  39.6 m/s 
B)  0.05 m/s 
C)  1568 m/s 
D)  28 m/s 
E)  ​40.09 m/s 
A)  39.6 m/s 
B)  0.05 m/s 
C)  1568 m/s 
D)  28 m/s 
E)  ​40.09 m/s

Question 17

A pole vaulter clears 4.00 m.With what speed does he strike the mat in the landing area?

Accepted Answer

A)  78.4 m/s 
B)  6.3 m/s 
C)  8.9 m/s 
D)  4.4 m/s 
E)  ​0.2 m/s 
A)  78.4 m/s 
B)  6.3 m/s 
C)  8.9 m/s 
D)  4.4 m/s 
E)  ​0.2 m/s

Question 18

As an object is lowered into a deep hole in the surface of the earth,which of the following must be assumed in regard to its potential energy?

Accepted Answer

A)  increase 
B)  decrease 
C)  remain constant 
D)  cannot tell from the information given 
A)  increase 
B)  decrease 
C)  remain constant 
D)  cannot tell from the information given

Question 19

Which of the following is an example of a nonconservative force?

Accepted Answer

A)  gravity 
B)  magnetism 
C)  friction 
D)  Both choices A and B are valid. 
A)  gravity 
B)  magnetism 
C)  friction 
D)  Both choices A and B are valid.

Question 20

A 2,000-kg ore car rolls 50.0 m down a frictionless 10.0° incline.If there is a horizontal spring at the end of the incline,what spring constant is required to stop the ore car in a distance of 1.00 m?

Accepted Answer

A)  347 kN/m 
B)  334 kN/m 
C)  1969 kN/m 
D)  174 kN/m 
E)  87​ kN/m 
A)  347 kN/m 
B)  334 kN/m 
C)  1969 kN/m 
D)  174 kN/m 
E)  87​ kN/m

Exam 5: Energy

Water flows over a section of Niagara Falls at a rate of 1.20 × 106 kg/s and falls 51.0 m.What is the power dissipated by the waterfall?

If during a given physical process the only force acting on an object is friction,which of the following must be assumed in regard to the object's kinetic energy?

A speed boat requires 82 kW to move at a constant speed of 16 m/s.What is the resistive force of the water at this speed?

Rupel pushes a box 3.00 m by applying a 19.0-N horizontal force.What work does she do?

A simple pendulum,3.0 m in length,is released with a push when the support string is at an angle of 20° from the vertical.If the initial speed of the suspended mass is 1.3 m/s when at the release point,what is its speed at the bottom of the swing? (g = 9.8 m/s2)

A 180-hp engine can deliver,in SI units,an average power of ____.(1 hp = 746 W)

A Hooke's law spring is compressed a distance d and is used to launch a mass m vertically to a height h above its starting position.Under the same compression d,the spring is now used to launch a mass of 2m.How high does this second mass rise?

The rate at which work is done is equivalent to which of the following?

A professional skier reaches a speed of 55 m/s on a 30° ski slope.Ignoring friction,what was the minimum distance along the slope the skier would have had to travel,starting from rest? ​

If both mass and velocity of a ball are tripled,the kinetic energy is increased by a factor of:

A horizontal force of 81 N is applied to move a 47-kg cart across a 7.0-m level surface.What work is done by the 81-N force?

A girl and her bicycle have a total mass of 43.0 kg.At the top of the hill her speed is 5.0 m/s,and her speed doubles as she rides down the hill.The hill is 15.0 m high and 100 m long.How much kinetic energy and potential energy is lost to friction?

The net force acting on a 4.0-kg object is given by Fx = (10 − x)N,where Fx is in newtons and x is in meters.How much work is done on the object as it moves from x = 0 to x = 15 m?

Two blocks are released from the top of a building.One falls straight down while the other slides down a smooth ramp.If all friction is ignored,which one is moving faster when it reaches the bottom?

A baseball catcher puts on an exhibition by catching a 0.10-kg ball dropped from a helicopter at a height of 81 m.What is the speed of the ball just before it hits the catcher's glove 1 m above the ground? (g = 9.8 m/s2 and ignore air resistance)

A pole vaulter clears 4.00 m.With what speed does he strike the mat in the landing area?

As an object is lowered into a deep hole in the surface of the earth,which of the following must be assumed in regard to its potential energy?

Which of the following is an example of a nonconservative force?

A 2,000-kg ore car rolls 50.0 m down a frictionless 10.0° incline.If there is a horizontal spring at the end of the incline,what spring constant is required to stop the ore car in a distance of 1.00 m?

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: 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

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

Water flows over a section of Niagara Falls at a rate of 1.20 × 10⁶ kg/s and falls 51.0 m.What is the power dissipated by the waterfall?

A simple pendulum,3.0 m in length,is released with a push when the support string is at an angle of 20° from the vertical.If the initial speed of the suspended mass is 1.3 m/s when at the release point,what is its speed at the bottom of the swing? (g = 9.8 m/s²)

A professional skier reaches a speed of 55 m/s on a 30° ski slope.Ignoring friction,what was the minimum distance along the slope the skier would have had to travel,starting from rest?

The net force acting on a 4.0-kg object is given by F_x = (10 − x)N,where F_x is in newtons and x is in meters.How much work is done on the object as it moves from x = 0 to x = 15 m?

A baseball catcher puts on an exhibition by catching a 0.10-kg ball dropped from a helicopter at a height of 81 m.What is the speed of the ball just before it hits the catcher's glove 1 m above the ground? (g = 9.8 m/s² and ignore air resistance)