Question 1

If a dense 20.0-kg object is falling in air at half its terminal velocity,what is the drag force on the object at this moment?

Accepted Answer

A) 24.5 N 
B) 49.0 N 
C) 69.3 N 
D) 98.0 N 
E) 139 N 
A) 24.5 N 
B) 49.0 N 
C) 69.3 N 
D) 98.0 N 
E) 139 N B

Question 2

An object attached to the end of a string swings in a vertical circle (R = 1.2 m),as shown.At an instant when θ = 30°,the speed of the object is 5.1 m/s and the tension in the string has a magnitude of 20 N.What is the mass of the object?

Accepted Answer

A) 2.0 kg 
B) 1.5 kg 
C) 1.8 kg 
D) 1.2 kg 
E) 0.80 kg 
A) 2.0 kg 
B) 1.5 kg 
C) 1.8 kg 
D) 1.2 kg 
E) 0.80 kg D

Question 3

The equation below is the solution to a problem.  
)
The best physical representation of this equation is

Accepted Answer

A) a sphere of 2.00 kg mass under a 45.2 N tension when at the bottom of a vertical circle. 
B) a sphere of 2.00 kg mass under a 45.2 N tension when at the side of a vertical circle. 
C) a sphere of 2.00 kg mass under a 45.2 N tension when at the top of a vertical circle. 
D) a sphere of 2.00 kg mass at any point on a horizontal circle. 
E) a 2.00 kg gecko running on the ceiling with a speed of 8.00 m/s. 
A) a sphere of 2.00 kg mass under a 45.2 N tension when at the bottom of a vertical circle. 
B) a sphere of 2.00 kg mass under a 45.2 N tension when at the side of a vertical circle. 
C) a sphere of 2.00 kg mass under a 45.2 N tension when at the top of a vertical circle. 
D) a sphere of 2.00 kg mass at any point on a horizontal circle. 
E) a 2.00 kg gecko running on the ceiling with a speed of 8.00 m/s. A

Question 4

A rock attached to a string swings in a vertical circle.Which free body diagram could correctly describe the force(s)on the rock when it is at the highest point?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 5

A 4.0-kg mass on the end of a string rotates in a circular motion on a horizontal frictionless table.The mass has a constant speed of 2.0 m/s and the radius of the circle is 0.80 m.What is the magnitude of the resultant force acting on the mass?

Accepted Answer

A) 39 N 
B) 20 N 
C) 44 N 
D) 0 N 
E) 30 N 
A) 39 N 
B) 20 N 
C) 44 N 
D) 0 N 
E) 30 N

Question 6

A space station in the form of a large wheel,120 m in diameter,rotates to provide an "artificial gravity" of 3.00 m/s2 for persons located at the outer rim.Find the rotational frequency of the wheel (in revolutions per minute)that will produce this effect.

Accepted Answer

Question 7

An airplane pilot experiences weightlessness as she passes over the top of a loop-the-loop maneuver.If her speed is 200 m/s at the time,find the radius of the loop.

Accepted Answer

The answer of An airplane pilot experiences weightlessness as she...

Question 8

A race car travels 40 m/s around a banked (45° with the horizontal)circular (radius = 0.20 km)track.What is the magnitude of the resultant force on the 80-kg driver of this car?

Accepted Answer

A) 0.68 kN 
B) 0.64 kN 
C) 0.72 kN 
D) 0.76 kN 
E) 0.52 kN 
A) 0.68 kN 
B) 0.64 kN 
C) 0.72 kN 
D) 0.76 kN 
E) 0.52 kN

Question 9

A roller-coaster car has a mass of 500 kg when fully loaded with passengers.The car passes over a hill of radius 15 m,as shown.At the top of the hill,the car has a speed of 8.0 m/s.What is the force of the track on the car at the top of the hill?

Accepted Answer

A) 7.0 kN up 
B) 7.0 kN down 
C) 2.8 kN down 
D) 2.8 kN up 
E) 5.6 kN down 
A) 7.0 kN up 
B) 7.0 kN down 
C) 2.8 kN down 
D) 2.8 kN up 
E) 5.6 kN down

Question 10

A roller-coaster car has a mass of 500 kg when fully loaded with passengers.At the bottom of a circular dip of radius 40 m (as shown in the figure)the car has a speed of 16 m/s.What is the magnitude of the force of the track on the car at the bottom of the dip?

Accepted Answer

A) 3.2 kN 
B) 8.1 kN 
C) 4.9 kN 
D) 1.7 kN 
E) 5.3 kN 
A) 3.2 kN 
B) 8.1 kN 
C) 4.9 kN 
D) 1.7 kN 
E) 5.3 kN

Question 11

The equation below is the solution to a problem.  
)
The best physical representation of this equation is

Accepted Answer

A) a sphere of 2.00 kg mass under a 6.00 N tension when at the bottom of a vertical circle. 
B) a sphere of 2.00 kg mass under a 6.00 N tension when at the side of a vertical circle. 
C) a sphere of 2.00 kg mass under a 6.00 N tension when at the top of a vertical circle. 
D) a sphere of 2.00 kg mass at any point on a horizontal circle. 
E) a 2.00 kg gecko running on the ceiling with a speed of 8.00 m/s. 
A) a sphere of 2.00 kg mass under a 6.00 N tension when at the bottom of a vertical circle. 
B) a sphere of 2.00 kg mass under a 6.00 N tension when at the side of a vertical circle. 
C) a sphere of 2.00 kg mass under a 6.00 N tension when at the top of a vertical circle. 
D) a sphere of 2.00 kg mass at any point on a horizontal circle. 
E) a 2.00 kg gecko running on the ceiling with a speed of 8.00 m/s.

Question 12

A 0.20-kg object attached to the end of a string swings in a vertical circle (radius = 80 cm).At the top of the circle the speed of the object is 4.5 m/s.What is the magnitude of the tension in the string at this position?

Accepted Answer

A) 7.0 N 
B) 2.0 N 
C) 3.1 N 
D) 5.1 N 
E) 6.6 N 
A) 7.0 N 
B) 2.0 N 
C) 3.1 N 
D) 5.1 N 
E) 6.6 N

Question 13

A race car starts from rest on a circular track of radius 400 m.Its speed increases at the constant rate of 0.500 m/s2.At the point where the magnitudes of the radial and tangential accelerations are equal,determine (a)the speed of the race car,and (b)the elapsed time.

Accepted Answer

Question 14

The equation below is the solution to a problem.  
)
The best physical representation of this equation is

Accepted Answer

A) a sphere of 2.00 kg mass under a 25.6 N tension when at the bottom of a vertical circle. 
B) a sphere of 2.00 kg mass under a 25.6 N tension when at the side of a vertical circle. 
C) a sphere of 2.00 kg mass under a 25.6 N tension when at the top of a vertical circle. 
D) a sphere of 2.00 kg mass at any point on a horizontal circle. 
E) a 2.00 kg gecko running on the ceiling with a speed of 8.00 m/s. 
A) a sphere of 2.00 kg mass under a 25.6 N tension when at the bottom of a vertical circle. 
B) a sphere of 2.00 kg mass under a 25.6 N tension when at the side of a vertical circle. 
C) a sphere of 2.00 kg mass under a 25.6 N tension when at the top of a vertical circle. 
D) a sphere of 2.00 kg mass at any point on a horizontal circle. 
E) a 2.00 kg gecko running on the ceiling with a speed of 8.00 m/s.

Question 15

Two small cylindrical plastic containers with flat bottoms are placed on a turntable that has a smooth flat surface.Canister A is empty;canister B contains lead shot.Each canister is the same distance r from the center.The coefficient of static friction between the canisters and the turntable is μs.When the speed of the turntable is gradually increased,

Accepted Answer

A) only the lighter container slides outward off the turntable;the heavier one stays on. 
B) only the heavier container slides outward off the turntable;the lighter one stays on. 
C) both containers slide off the turntable at the same turntable speed. 
D) the lighter container slides inward. 
E) the heavier container slides inward. 
A) only the lighter container slides outward off the turntable;the heavier one stays on. 
B) only the heavier container slides outward off the turntable;the lighter one stays on. 
C) both containers slide off the turntable at the same turntable speed. 
D) the lighter container slides inward. 
E) the heavier container slides inward.

Question 16

For a plane to be able to fly clockwise in a horizontal circle as seen from above,in addition to exerting a force downwards on the air

Accepted Answer

A) it must be increasing its speed. 
B) it must exert a force on the air that is directed to the plane's left side. 
C) it must exert a force on the air that is directed to the plane's right side. 
D) it does not need to exert a force: it must only move the wing flaps out. 
E) it only needs to deflect the air without exerting any additional force on the air. 
A) it must be increasing its speed. 
B) it must exert a force on the air that is directed to the plane's left side. 
C) it must exert a force on the air that is directed to the plane's right side. 
D) it does not need to exert a force: it must only move the wing flaps out. 
E) it only needs to deflect the air without exerting any additional force on the air.

Question 17

The coefficient of static friction for the tires of a race car is 0.950 and the coefficient of kinetic friction is 0.800.The car is on a level circular track of 50.0 m radius on a planet where  
Compared to Earth's  
)The maximum safe speed on the track on the planet is ____ times as large as the maximum safe speed on Earth.

Accepted Answer

A) 0.250 
B) 0.500 
C) 1.00 
D) 2.00 
E) 4.00 
A) 0.250 
B) 0.500 
C) 1.00 
D) 2.00 
E) 4.00

Question 18

A 0.50-kg mass attached to the end of a string swings in a vertical circle (radius = 2.0 m).When the string is horizontal,the speed of the mass is 8.0 m/s.What is the magnitude of the force of the string on the mass at this position?

Accepted Answer

A) 16 N 
B) 17 N 
C) 21 N 
D) 11 N 
E) 25 N 
A) 16 N 
B) 17 N 
C) 21 N 
D) 11 N 
E) 25 N

Question 19

An iceboat is traveling in a circle on the ice.Halfway around the circle the sail and the steering mechanism fall off the boat.Which statement is correct?

Accepted Answer

A) The boat will continue traveling in the circle because there is no friction. 
B) The boat will continue to travel in the circle because its velocity exerts a force on it. 
C) The boat will move off on a line tangent to the circle because there is no force on it. 
D) The boat will move off tangent to the circle because there is a force on it perpendicular to the boat directed to the outside of the circle. 
E) The boat will move off to the outside perpendicular to the tangent line since a force directed to the outside of the circle always acts on the boat. 
A) The boat will continue traveling in the circle because there is no friction. 
B) The boat will continue to travel in the circle because its velocity exerts a force on it. 
C) The boat will move off on a line tangent to the circle because there is no force on it. 
D) The boat will move off tangent to the circle because there is a force on it perpendicular to the boat directed to the outside of the circle. 
E) The boat will move off to the outside perpendicular to the tangent line since a force directed to the outside of the circle always acts on the boat.

Question 20

If a 20-kg object dropped in air has a terminal speed of 60 m/s,what was its acceleration at 30 m/s?

Accepted Answer

A) 9.80 m/s2 
B) 7.35 m/s2 
C) 4.90 m/s2 
D) 2.45 m/s2 
E) More information is needed to answer this question. 
A) 9.80 m/s2 
B) 7.35 m/s2 
C) 4.90 m/s2 
D) 2.45 m/s2 
E) More information is needed to answer this question.

Exam 6: Circular Motion and Other Applications of Newtons Laws

If a dense 20.0-kg object is falling in air at half its terminal velocity,what is the drag force on the object at this moment?

An object attached to the end of a string swings in a vertical circle (R = 1.2 m),as shown.At an instant when θ = 30°,the speed of the object is 5.1 m/s and the tension in the string has a magnitude of 20 N.What is the mass of the object?

The equation below is the solution to a problem. ) The best physical representation of this equation is

A rock attached to a string swings in a vertical circle.Which free body diagram could correctly describe the force(s)on the rock when it is at the highest point?

A 4.0-kg mass on the end of a string rotates in a circular motion on a horizontal frictionless table.The mass has a constant speed of 2.0 m/s and the radius of the circle is 0.80 m.What is the magnitude of the resultant force acting on the mass?

A space station in the form of a large wheel,120 m in diameter,rotates to provide an "artificial gravity" of 3.00 m/s2 for persons located at the outer rim.Find the rotational frequency of the wheel (in revolutions per minute)that will produce this effect.

An airplane pilot experiences weightlessness as she passes over the top of a loop-the-loop maneuver.If her speed is 200 m/s at the time,find the radius of the loop.

A race car travels 40 m/s around a banked (45° with the horizontal)circular (radius = 0.20 km)track.What is the magnitude of the resultant force on the 80-kg driver of this car?

A roller-coaster car has a mass of 500 kg when fully loaded with passengers.The car passes over a hill of radius 15 m,as shown.At the top of the hill,the car has a speed of 8.0 m/s.What is the force of the track on the car at the top of the hill?

A roller-coaster car has a mass of 500 kg when fully loaded with passengers.At the bottom of a circular dip of radius 40 m (as shown in the figure)the car has a speed of 16 m/s.What is the magnitude of the force of the track on the car at the bottom of the dip?

The equation below is the solution to a problem. ) The best physical representation of this equation is

A 0.20-kg object attached to the end of a string swings in a vertical circle (radius = 80 cm).At the top of the circle the speed of the object is 4.5 m/s.What is the magnitude of the tension in the string at this position?

A race car starts from rest on a circular track of radius 400 m.Its speed increases at the constant rate of 0.500 m/s2.At the point where the magnitudes of the radial and tangential accelerations are equal,determine (a)the speed of the race car,and (b)the elapsed time.

The equation below is the solution to a problem. ) The best physical representation of this equation is

For a plane to be able to fly clockwise in a horizontal circle as seen from above,in addition to exerting a force downwards on the air

A 0.50-kg mass attached to the end of a string swings in a vertical circle (radius = 2.0 m).When the string is horizontal,the speed of the mass is 8.0 m/s.What is the magnitude of the force of the string on the mass at this position?

An iceboat is traveling in a circle on the ice.Halfway around the circle the sail and the steering mechanism fall off the boat.Which statement is correct?

If a 20-kg object dropped in air has a terminal speed of 60 m/s,what was its acceleration at 30 m/s?

Physics and Measurement

Motion in One Dimension

Vectors

Motion in Two Dimensions

The Laws of Motion

Energy of a System

Conservation of Energy

Linear Momentum and Collisions

Rotation of a Rigid Object About a Fixed Axis

Angular Momentum

Static Equilibrium and Elasticity

Universal Gravitation

Fluid Mechanics

Oscillatory Motion

Wave Motion

Sound Waves

Superposition and Standing Waves

Temperature

The First Law of Thermodynamics

The Kinetic Theory of Gases

Heat Engines, entropy, and the Second Law of Thermodynamics

Electric Fields

Gausss Law

Electric Potential

Capacitance and Dielectrics

Current and Resistance

Direct-Current Circuits

Magnetic Fields

Sources of the Magnetic Field

Faradays Law

Inductance

Alternating-Current Circuits

Electromagnetic Waves

The Nature of Light and the Principles of Ray Optics

Image Formation

Wave Optics

Diffraction Patterns and Polarization

Relativity

Introduction to Quantum Physics

Quantum Mechanics

Atomic Physics

Molecules and Solids

Nuclear Structure

Applications of Nuclear Physics

Particle Physics and Cosmology

Filters

A space station in the form of a large wheel,120 m in diameter,rotates to provide an "artificial gravity" of 3.00 m/s² for persons located at the outer rim.Find the rotational frequency of the wheel (in revolutions per minute)that will produce this effect.

A race car starts from rest on a circular track of radius 400 m.Its speed increases at the constant rate of 0.500 m/s².At the point where the magnitudes of the radial and tangential accelerations are equal,determine (a)the speed of the race car,and (b)the elapsed time.