Question 1

The value of the average velocity for any round trip is equal to

Accepted Answer

A)  Total distance traveled divided by total trip time. 
B)  The final acceleration multiplied by trip time 
C)  Zero. 
D)  The person's speed halfway through the path. 
A)  Total distance traveled divided by total trip time. 
B)  The final acceleration multiplied by trip time 
C)  Zero. 
D)  The person's speed halfway through the path. C

Question 2

A child throws a ball perfectly horizontally at the same time a dirt clod falls off it at the same height above the ground. The clod falls vertically downward. Ignoring air resistance, the time when the clod hits the ground will

Accepted Answer

A)  be equal to the time the ball hits the ground 
B)  be earlier than when the ball hits 
C)  be later than when the ball hits 
D)  not depend upon how high it started falling from 
A)  be equal to the time the ball hits the ground 
B)  be earlier than when the ball hits 
C)  be later than when the ball hits 
D)  not depend upon how high it started falling from A

Question 3

Suppose Larissa throws a ball up in the air and it comes back down to the same place she threw it from. Ignoring times when the ball is in contact with her hand, and ignoring air resistance (friction with the air), identify the point(s) of
-Maximum and minimum kinetic energy.

Accepted Answer

The maximum kinetic energy occurs at the point where the ball is moving fastest, namely right after it leaves Larissa's hand and right before she catches it. The minimum kinetic energy will occur when the ball is moving slowest - right at the top of the path where it instantaneously stops.

Question 4

A friend is casually talking with you about physics concepts and brings up the following claim. They say that average speed for a trip is total distance divided by total time, which is true. Then they say that if the trip consists of a person traveling at two different speeds for two different times then you can get the average speed by just finding the average speeds for the two parts of the trip and then take their average. Is their claim true? Please explain.

Accepted Answer

Their claim is not true becaus

Question 5

In our calculations of motion, we have ignored certain aspects of the object and its environment. Please briefly discuss three such aspects, and what kind of differences they make.

Accepted Answer

One aspect is air resistance, or drag. T

Question 6

A projectile is thrown directly upward and caught again. At the top of its path

Accepted Answer

A)  it stops accelerating 
B)  its vertical velocity is zero 
C)  its horizontal velocity changes 
D)  its acceleration changes 
A)  it stops accelerating 
B)  its vertical velocity is zero 
C)  its horizontal velocity changes 
D)  its acceleration changes

Question 7

Suppose you are on another planet and you want to measure its acceleration of gravity so you drop an object from rest. It hits the ground, traveling a distance of 0.8 m in 0.5 second and then bounces back up and stops exactly where it started from.
-When distance is divided by time the result is 1.6 m/sec. Please explain why this result does not agree with the answer in (D).

Accepted Answer

This is because d/t gives us the average

Question 8

A friend states Newton's First Law of Motion as "An object will move in a straight line unless acted upon by a force" Please evaluate the scientific merit of his statement.

Accepted Answer

the friend is almost right but has left

Question 9

A frequent flyer is suing an airline. She claims that during landing, the plane's rapid acceleration caused a suitcase on a luggage rack in front of her to fly backwards and hit her. Using any of Newton's laws of motion, please support or refute the passenger's claim.

Accepted Answer

Here I would use Newton's first law of m

Question 10

Suppose you are on another planet and you want to measure its acceleration of gravity so you drop an object from rest. It hits the ground, traveling a distance of 0.8 m in 0.5 second and then bounces back up and stops exactly where it started from.
-Taking downward to be positive, how does the ball's average speed compare to the magnitude of its average velocity on the way down?

Accepted Answer

On the way down the average sp

Question 11

You are riding on a flat train car and are climbing up the side of a hay stack. You are half way up the stack and are maintaining a steady height. You and the stack are moving steadily along the straight tracks at constant speed. The net force on you is

Accepted Answer

A)  downhill-toward the bottom of the front of the stack. 
B)  zero. 
C)  uphill-behind you. 
D)  horizontal-parallel to the tracks. 
A)  downhill-toward the bottom of the front of the stack. 
B)  zero. 
C)  uphill-behind you. 
D)  horizontal-parallel to the tracks.

Question 12

Suppose you are a football player and you kick a ball for a field goal. Ignoring air resistance, the ball's horizontal velocity

Accepted Answer

A)  changes throughout the path due to gravitational acceleration 
B)  is zero at the top of the path 
C)  is maximum at the top of the path 
D)  remains constant throughout the path 
A)  changes throughout the path due to gravitational acceleration 
B)  is zero at the top of the path 
C)  is maximum at the top of the path 
D)  remains constant throughout the path

Question 13

Suppose you push a 50 kg box 10 m up a frictionless incline that has a 10% grade. What is the change in potential energy for the box?

Accepted Answer

A)  500 J 
B)  5000 J 
C)  250 J 
D)  2500 J 
A)  500 J 
B)  5000 J 
C)  250 J 
D)  2500 J

Question 14

Suppose your car is on a 5% grade, meaning that for every 100 m you travel along the road you raise or lower only 5 m in elevation. If your car weighs 1500 kg, what is the component of its weight parallel to the road?

Accepted Answer

A)  15000 N 
B)  1500 N 
C)  7500 N 
D)  750 N 
A)  15000 N 
B)  1500 N 
C)  7500 N 
D)  750 N

Question 15

Suppose you weigh 986 N. How much force does the Earth exert on you, if any?

Accepted Answer

A)  it cannot be determined 
B)  986 N 
C)  98.6N 
D)  none 
A)  it cannot be determined 
B)  986 N 
C)  98.6N 
D)  none

Question 16

A gymnast jumps upward with an initial speed of 10 m/s. She is in the air for a total time of

Accepted Answer

A)  1 second 
B)  5 seconds 
C)  2 seconds 
D)  10 seconds 
A)  1 second 
B)  5 seconds 
C)  2 seconds 
D)  10 seconds

Question 17

Suppose you use a ramp to lift a 200 kg object. You raise it 2 m above the ground and did 5000 J of work. Assuming that gravity and friction could be the only forces you had to work against, was there any friction, and if so how much work did you have to do against it?

Accepted Answer

Yes there was friction because

Question 18

Suppose you are driving north and suddenly hit your brakes to avoid a dog in the road. As you come to a stop your acceleration is directed

Accepted Answer

A)  North 
B)  South 
C)  Nowhere because acceleration is a scalar 
D)  Downwards 
A)  North 
B)  South 
C)  Nowhere because acceleration is a scalar 
D)  Downwards

Question 19

Suppose you throw a ball upwards with a certain initial speed from a certain height h above the ground, and you wait for it to go up, stop and come back down to the same (initial) position. Including air resistance, how will its speed hitting the ground on the way back down compare to its launch speed? Please explain.

Accepted Answer

Its speed hitting the ground on the way

Question 20

Your friend and you are at the mall shopping. She stops, grabs your arm and exclaims that she is worried about her physics test she took last Friday because she ignored the work done by (or against) the normal force when an object slides across a surface. What would you (correctly) reply to her?

Accepted Answer

I would say (correctly) that the normal

The value of the average velocity for any round trip is equal to

A child throws a ball perfectly horizontally at the same time a dirt clod falls off it at the same height above the ground. The clod falls vertically downward. Ignoring air resistance, the time when the clod hits the ground will

Suppose Larissa throws a ball up in the air and it comes back down to the same place she threw it from. Ignoring times when the ball is in contact with her hand, and ignoring air resistance (friction with the air), identify the point(s) of -Maximum and minimum kinetic energy.

In our calculations of motion, we have ignored certain aspects of the object and its environment. Please briefly discuss three such aspects, and what kind of differences they make.

A projectile is thrown directly upward and caught again. At the top of its path

A friend states Newton's First Law of Motion as "An object will move in a straight line unless acted upon by a force" Please evaluate the scientific merit of his statement.

A frequent flyer is suing an airline. She claims that during landing, the plane's rapid acceleration caused a suitcase on a luggage rack in front of her to fly backwards and hit her. Using any of Newton's laws of motion, please support or refute the passenger's claim.

You are riding on a flat train car and are climbing up the side of a hay stack. You are half way up the stack and are maintaining a steady height. You and the stack are moving steadily along the straight tracks at constant speed. The net force on you is

Suppose you are a football player and you kick a ball for a field goal. Ignoring air resistance, the ball's horizontal velocity

Suppose you push a 50 kg box 10 m up a frictionless incline that has a 10% grade. What is the change in potential energy for the box?

Suppose your car is on a 5% grade, meaning that for every 100 m you travel along the road you raise or lower only 5 m in elevation. If your car weighs 1500 kg, what is the component of its weight parallel to the road?

Suppose you weigh 986 N. How much force does the Earth exert on you, if any?

A gymnast jumps upward with an initial speed of 10 m/s. She is in the air for a total time of

Suppose you use a ramp to lift a 200 kg object. You raise it 2 m above the ground and did 5000 J of work. Assuming that gravity and friction could be the only forces you had to work against, was there any friction, and if so how much work did you have to do against it?

Suppose you are driving north and suddenly hit your brakes to avoid a dog in the road. As you come to a stop your acceleration is directed

Your friend and you are at the mall shopping. She stops, grabs your arm and exclaims that she is worried about her physics test she took last Friday because she ignored the work done by (or against) the normal force when an object slides across a surface. What would you (correctly) reply to her?

The Laws of Motion, Part 2

Mechanical Objects, Part 1

Mechanical Objects, Part 2

Fluids

Fluids and Motion

Heat and Phase Transitions

Thermodynamics

Resonance and Mechanical Waves

Electricity

Magnetism and Electrodynamics

Electromagnetic Waves

Light

Optics and Electronics

Modern Physics

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Exam 1: The Laws of Motion, Part 1

The value of the average velocity for any round trip is equal to

A child throws a ball perfectly horizontally at the same time a dirt clod falls off it at the same height above the ground. The clod falls vertically downward. Ignoring air resistance, the time when the clod hits the ground will

Suppose Larissa throws a ball up in the air and it comes back down to the same place she threw it from. Ignoring times when the ball is in contact with her hand, and ignoring air resistance (friction with the air), identify the point(s) of -Maximum and minimum kinetic energy.

In our calculations of motion, we have ignored certain aspects of the object and its environment. Please briefly discuss three such aspects, and what kind of differences they make.

A projectile is thrown directly upward and caught again. At the top of its path

A friend states Newton's First Law of Motion as "An object will move in a straight line unless acted upon by a force" Please evaluate the scientific merit of his statement.

A frequent flyer is suing an airline. She claims that during landing, the plane's rapid acceleration caused a suitcase on a luggage rack in front of her to fly backwards and hit her. Using any of Newton's laws of motion, please support or refute the passenger's claim.

You are riding on a flat train car and are climbing up the side of a hay stack. You are half way up the stack and are maintaining a steady height. You and the stack are moving steadily along the straight tracks at constant speed. The net force on you is

Suppose you are a football player and you kick a ball for a field goal. Ignoring air resistance, the ball's horizontal velocity

Suppose you push a 50 kg box 10 m up a frictionless incline that has a 10% grade. What is the change in potential energy for the box?

Suppose your car is on a 5% grade, meaning that for every 100 m you travel along the road you raise or lower only 5 m in elevation. If your car weighs 1500 kg, what is the component of its weight parallel to the road?

Suppose you weigh 986 N. How much force does the Earth exert on you, if any?

A gymnast jumps upward with an initial speed of 10 m/s. She is in the air for a total time of

Suppose you use a ramp to lift a 200 kg object. You raise it 2 m above the ground and did 5000 J of work. Assuming that gravity and friction could be the only forces you had to work against, was there any friction, and if so how much work did you have to do against it?

Suppose you are driving north and suddenly hit your brakes to avoid a dog in the road. As you come to a stop your acceleration is directed

Your friend and you are at the mall shopping. She stops, grabs your arm and exclaims that she is worried about her physics test she took last Friday because she ignored the work done by (or against) the normal force when an object slides across a surface. What would you (correctly) reply to her?

The Laws of Motion, Part 2

Mechanical Objects, Part 1

Mechanical Objects, Part 2

Fluids

Fluids and Motion

Heat and Phase Transitions

Thermodynamics

Resonance and Mechanical Waves

Electricity

Magnetism and Electrodynamics

Electromagnetic Waves

Light

Optics and Electronics

Modern Physics

Filters