Question 1

A 1 000-kg sports car accelerates from zero to 28 m/s in 7.0 s.What is the average power delivered by the automobile engine?

Accepted Answer

A)  112 kW 
B)  2 kW 
C)  56 kW 
D)  196 kW 
E)  ​66 kW 
A)  112 kW 
B)  2 kW 
C)  56 kW 
D)  196 kW 
E)  ​66 kW

Question 2

Three different mass projectiles are launched from the top of a building each at different angles of elevation.Each particle has the same initial kinetic energy.Which particle has the greatest speed just as it impacts with the ground?

Accepted Answer

A)  The one launched at the highest angle of elevation. 
B)  The one with the highest mass. 
C)  The one with the lowest mass. 
D)  They all will have the same speed on impact. 
A)  The one launched at the highest angle of elevation. 
B)  The one with the highest mass. 
C)  The one with the lowest mass. 
D)  They all will have the same speed on impact.

Question 3

A rock is thrown straight up with an initial velocity of 14 m/s.Ignore energy lost to air friction.How high will the rock rise?

Accepted Answer

A)  7 m 
B)  98 m 
C)  20 m 
D)  10 m 
E)  ​0.1 m 
A)  7 m 
B)  98 m 
C)  20 m 
D)  10 m 
E)  ​0.1 m

Question 4

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 double the compression,the spring is now used to launch the mass.How high does the mass now rise above its starting position?

Accepted Answer

A)  2 h 
B)  1.41 h 
C)  3 h 
D)  4 h 
A)  2 h 
B)  1.41 h 
C)  3 h 
D)  4 h

Question 5

A 1.00-kg ball has zero kinetic and potential energy.Ernie drops the ball into a 10.0-m-deep well.Just before the ball hits the bottom,the sum of its kinetic and potential energy is:

Accepted Answer

A)  zero. 
B)  98 J. 
C)  −98 J. 
D)  196 J. 
E)  ​- 196 J. 
A)  zero. 
B)  98 J. 
C)  −98 J. 
D)  196 J. 
E)  ​- 196 J.

Question 6

In a problem using energy considerations to solve for the speed of a ball thrown from the top of a building when it strikes the ground below,where should the potential energy have its zero value?

Accepted Answer

A)  It should be at the level from where the ball is thrown. 
B)  It should be at the ground level where the ball hits. 
C)  It should be slightly below ground level so the potential energy is always positive. 
D)  It doesn't matter since only differences in potential energy matter in solutions. 
A)  It should be at the level from where the ball is thrown. 
B)  It should be at the ground level where the ball hits. 
C)  It should be slightly below ground level so the potential energy is always positive. 
D)  It doesn't matter since only differences in potential energy matter in solutions.

Question 7

The net force acting on a 13.0-kg object is given by Fx = (20 − 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 = 13 m?

Accepted Answer

A)  7 J 
B)  91 J 
C)  175.5 J 
D)  149 J 
E)  ​87.75 J 
A)  7 J 
B)  91 J 
C)  175.5 J 
D)  149 J 
E)  ​87.75 J

Question 8

Adisa pulls a 40-N crate up a 6.0-m long inclined plane at a constant velocity.If the plane is inclined at an angle of 38° to the horizontal and there is a constant force of friction of 10 N between the crate and the surface,what is the net change in potential energy of the crate?

Accepted Answer

A)  148 J 
B)  −148 J 
C)  189 J 
D)  −189 J 
E)  ​None of these 
A)  148 J 
B)  −148 J 
C)  189 J 
D)  −189 J 
E)  ​None of these

Question 9

A 60-kg woman runs up a flight of stairs having a rise of 4.5 m in a time of 4.3 s.What average power did she supply?

Accepted Answer

A)  63 W 
B)  615 W 
C)  562 W 
D)  625 W 
E)  ​605 W 
A)  63 W 
B)  615 W 
C)  562 W 
D)  625 W 
E)  ​605 W

Question 10

Yuri,a Russian weightlifter,is able to lift 265 kg 2.20 m in 2.10 s.What is his power output?

Accepted Answer

A)  583.00 W 
B)  2.72 kW 
C)  1.18 kW 
D)  12.00 kW 
E)  ​27.21 kW 
A)  583.00 W 
B)  2.72 kW 
C)  1.18 kW 
D)  12.00 kW 
E)  ​27.21 kW

Question 11

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

Accepted Answer

A)  h 
B)  2 h 
C)  3 h 
D)  4 h 
A)  h 
B)  2 h 
C)  3 h 
D)  4 h

Question 12

A force of 5.0 N is applied to a 20-kg mass on a horizontal frictionless surface.As the speed of the mass increases at a constant acceleration,the power delivered to it by the force:

Accepted Answer

A)  remains the same. 
B)  increases. 
C)  decreases. 
D)  doubles every 4.0 seconds. 
A)  remains the same. 
B)  increases. 
C)  decreases. 
D)  doubles every 4.0 seconds.

Question 13

A very light cart holding a 200-N box is moved at constant velocity across a 20-m level surface.What is the net work done in the process?

Accepted Answer

A)  zero 
B)  1/10 J 
C)  10 J 
D)  100 J 
E)  ​4000 J 
A)  zero 
B)  1/10 J 
C)  10 J 
D)  100 J 
E)  ​4000 J

Question 14

A baseball catcher puts on an exhibition by catching a 0.170-kg ball dropped from a helicopter at a height of 110 m above the catcher.If the catcher "gives" with the ball for a distance of 0.695 m while catching it,what average force is exerted on the mitt by the ball? (g = 9.80 m/s2)

Accepted Answer

A)  27 N 
B)  183 N 
C)  264 N 
D)  274 N 
E)  ​749 N 
A)  27 N 
B)  183 N 
C)  264 N 
D)  274 N 
E)  ​749 N

Question 15

A jet engine develops 1.1 × 105 N of thrust in moving an airplane forward at a speed of 850 km/h.What is the power developed by the engine?

Accepted Answer

A)  935 kW 
B)  259.7 MW 
C)  26 MW 
D)  31 MW 
E)  ​21 MW 
A)  935 kW 
B)  259.7 MW 
C)  26 MW 
D)  31 MW 
E)  ​21 MW

Question 16

The SI units for k,the spring constant,are equivalent to:

Accepted Answer

A)  J. 
B)  J / N. 
C)  kg / s2. 
D)  None of the above. 
A)  J. 
B)  J / N. 
C)  kg / s2. 
D)  None of the above.

Question 17

I use a rope 4.00 m long to swing a 8.0-kg weight around my head.The tension in the rope is 28.0 N.In half a revolution how much work is done by the rope on the weight?

Accepted Answer

A)  112 J 
B)  896 J 
C)  56 J 
D)  0 
E)  ​14 J 
A)  112 J 
B)  896 J 
C)  56 J 
D)  0 
E)  ​14 J

Question 18

A horizontal force of 200 N is applied to a 55-kg cart across a 15-m level surface.If the cart accelerates at 2.0 m/s2,then what is the work done by the force of friction as it acts to retard the motion of the cart?

Accepted Answer

A)  -4650 J 
B)  -1350 J 
C)  -3000 J 
D)  -90 J 
E)  ​-310 J 
A)  -4650 J 
B)  -1350 J 
C)  -3000 J 
D)  -90 J 
E)  ​-310 J

Question 19

When an object is dropped from a tower,what is the effect of the air resistance as it falls?

Accepted Answer

A)  does positive work 
B)  increases the object's kinetic energy 
C)  increases the object's potential energy 
D)  None of the above choices are valid. 
A)  does positive work 
B)  increases the object's kinetic energy 
C)  increases the object's potential energy 
D)  None of the above choices are valid.

Question 20

A Hooke's law spring is mounted horizontally over a frictionless surface.The spring is then compressed a distance d and is used to launch a mass m along the frictionless surface.What compression of the spring would result in the mass attaining double the kinetic energy received in the above situation?

Accepted Answer

A)  1.41 d 
B)  1.73 d 
C)  2.00 d 
D)  4.00 d 
A)  1.41 d 
B)  1.73 d 
C)  2.00 d 
D)  4.00 d

Exam 5: Energy

A 1 000-kg sports car accelerates from zero to 28 m/s in 7.0 s.What is the average power delivered by the automobile engine?

Three different mass projectiles are launched from the top of a building each at different angles of elevation.Each particle has the same initial kinetic energy.Which particle has the greatest speed just as it impacts with the ground?

A rock is thrown straight up with an initial velocity of 14 m/s.Ignore energy lost to air friction.How high will the rock rise?

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 double the compression,the spring is now used to launch the mass.How high does the mass now rise above its starting position?

A 1.00-kg ball has zero kinetic and potential energy.Ernie drops the ball into a 10.0-m-deep well.Just before the ball hits the bottom,the sum of its kinetic and potential energy is:

In a problem using energy considerations to solve for the speed of a ball thrown from the top of a building when it strikes the ground below,where should the potential energy have its zero value?

The net force acting on a 13.0-kg object is given by Fx = (20 − 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 = 13 m?

Adisa pulls a 40-N crate up a 6.0-m long inclined plane at a constant velocity.If the plane is inclined at an angle of 38° to the horizontal and there is a constant force of friction of 10 N between the crate and the surface,what is the net change in potential energy of the crate?

A 60-kg woman runs up a flight of stairs having a rise of 4.5 m in a time of 4.3 s.What average power did she supply?

Yuri,a Russian weightlifter,is able to lift 265 kg 2.20 m in 2.10 s.What is his power output?

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

A force of 5.0 N is applied to a 20-kg mass on a horizontal frictionless surface.As the speed of the mass increases at a constant acceleration,the power delivered to it by the force:

A very light cart holding a 200-N box is moved at constant velocity across a 20-m level surface.What is the net work done in the process?

A baseball catcher puts on an exhibition by catching a 0.170-kg ball dropped from a helicopter at a height of 110 m above the catcher.If the catcher "gives" with the ball for a distance of 0.695 m while catching it,what average force is exerted on the mitt by the ball? (g = 9.80 m/s2)

A jet engine develops 1.1 × 105 N of thrust in moving an airplane forward at a speed of 850 km/h.What is the power developed by the engine?

The SI units for k,the spring constant,are equivalent to:

I use a rope 4.00 m long to swing a 8.0-kg weight around my head.The tension in the rope is 28.0 N.In half a revolution how much work is done by the rope on the weight?

A horizontal force of 200 N is applied to a 55-kg cart across a 15-m level surface.If the cart accelerates at 2.0 m/s2,then what is the work done by the force of friction as it acts to retard the motion of the cart?

When an object is dropped from a tower,what is the effect of the air resistance as it falls?

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

The net force acting on a 13.0-kg object is given by F_x = (20 − 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 = 13 m?

A baseball catcher puts on an exhibition by catching a 0.170-kg ball dropped from a helicopter at a height of 110 m above the catcher.If the catcher "gives" with the ball for a distance of 0.695 m while catching it,what average force is exerted on the mitt by the ball? (g = 9.80 m/s²)

A jet engine develops 1.1 × 10⁵ N of thrust in moving an airplane forward at a speed of 850 km/h.What is the power developed by the engine?

A horizontal force of 200 N is applied to a 55-kg cart across a 15-m level surface.If the cart accelerates at 2.0 m/s²,then what is the work done by the force of friction as it acts to retard the motion of the cart?