Question 1

Suppose you have two cars, and the larger one is twice as massive as the smaller one. If you and a friend push on them so that their accelerations are equal, how must the forces applied to the cars compare?
A) The force on the larger car is equal to that on the smaller car
B) The force on the larger car is ½ that on the smaller car.
C) The force on the larger car is twice that on the smaller car.
D) The force on the larger car is more than three times that on the smaller car.

Accepted Answer

The force required to accelerate an object is directly proportional to its mass (F=ma), so if the larger car is twice as massive and they accelerate equally, the force on the larger car must be twice that on the smaller car.

Question 2

Which of the following devices on a car can be used to cause the car to accelerate?
A) The gas pedal
B) The brake pedal
C) The steering wheel
D) All the above

Accepted Answer

D

Question 3

The acceleration of an object is equal to
A) the rate of change of its position
B) the rate of change of its velocity
C) the rate of change of its speed only
D) the time an object has been in motion

Accepted Answer

Acceleration is defined as the rate at which an object's velocity changes with time.

Question 4

Suppose you are at a stop light and realize that an important antique physics textbook sale ends in five minutes. Naturally, you start off very rapidly. To you, some papers on the dashboard fly straight backwards. To an observer on the ground they
A) remained where they were.
B) moved forward rapidly.
C) moved backwards rapidly.
D) fell straight down.

Accepted Answer

To you, the papers fly straight backwards because you are accelerating forward. To an observer on the ground, the papers remain where they were because the ground is not accelerating.

Question 5

The SI units of acceleration are A) m/s B) kgm/s² C) m/s² D) kg m²/s²

Accepted Answer

Acceleration is defined as the rate of change of velocity with respect to time, which is measured in meters per second squared (m/s^2).

Question 6

Suppose you have a car traveling down the road at constant speed and not changing direction. It is experiencing gravity, wind resistance and frictional forces from the road. What can be said about the car's acceleration?
A) It is accelerating because there are forces acting on it.
B) It accelerating because the motor is running, propelling the car forward.
C) It is not accelerating because gravity holds it down.
D) It is not accelerating because it has constant velocity.

Accepted Answer

The car is not accelerating because it has a constant velocity, meaning its speed and direction are not changing. Forces like gravity, wind resistance, and friction do not necessarily mean acceleration if they are balanced and the velocity remains constant.

Question 7

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

Accepted Answer

When you hit your brakes to stop while driving north, your acceleration is directed opposite to your direction of motion, which is south. Acceleration is a vector quantity that describes the rate of change of velocity, including its direction.

Question 8

If you are backing up but slowing down, your acceleration is directed
A) backwards
B) nowhere
C) forwards
D) to the left

Accepted Answer

When you are backing up (moving backwards) and slowing down, it means you are decelerating in the direction of your motion (backwards). Deceleration is acceleration in the opposite direction of your motion. Therefore, if you are moving backwards and slowing down, your acceleration is directed forwards, opposing your motion.

Question 9

Under what conditions are the values of average speed and the magnitude of the average velocity equal?
A) When moving in a straight line
B) When moving in a straight line and not turning around
C) When moving in a circular path
D) When walking around the perimeter of a rectangle

Accepted Answer

The values of average speed and the magnitude of the average velocity are equal when the motion does not involve a change in direction, i.e., when moving in a straight line without turning around. This is because average velocity is displacement divided by time, and average speed is total distance divided by time. When there's no change in direction, displacement equals total distance.

Question 10

You are making a round trip from City A to City B and back to City A again at constant speed. At what point in the trip is your average speed equal to three times the magnitude of your average velocity?

Accepted Answer

The answer of You are making a round trip from...

Question 11

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

The answer of A frequent flyer is suing an airline....

Question 12

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 answer of A friend states Newton's First Law of...

Question 13

You walk in a given direction for 20 m during the first 5 seconds of a trip and then 15 m during the next 2 seconds. Your average speed is equal to
A) 8 m/s
B) 2 m/s
C) 5 m/s
D) -5 m/s

Accepted Answer

The total distance covered is 20 m + 15 m = 35 m, and the total time taken is 5 s + 2 s = 7 s. Average speed = Total distance / Total time = 35 m / 7 s = 5 m/s.

Question 14

To cause a 25 kg object to experience an acceleration of 2 m/s² the net force that needs to be applied to the object is A) 10 N B) 5 N C) 50 N D) 100 N

Accepted Answer

The correct answer is found by using Newton's second law of motion, F = ma, where F is the force applied, m is the mass of the object, and a is the acceleration. Substituting the given values, F = 25 kg * 2 m/s^2 = 50 N.

Question 15

A net force of 8 N is applied to a 2 kg object. The object's acceleration is A) 4 m/s² B) 8 m/s² C) 16 m/s² D) 2 m/s²

Accepted Answer

The acceleration can be calculated using Newton's second law of motion, $F = ma$, where $F$ is the force applied, $m$ is the mass of the object, and $a$ is the acceleration. Substituting the given values, $8 \, \text{N} = 2 \, \text{kg} \cdot a$, solving for $a$ gives $a = 4 \, \text{m/s}^2$.

Question 16

An object experiences a net force of 20 N and has an acceleration of 4 m/s². The object's mass must be A) 20 kg B) 5 kg C) 80 kg D) 2 kg

Accepted Answer

The object's mass can be calculated using Newton's second law of motion, F = ma, where F is the force applied, m is the mass of the object, and a is the acceleration. Rearranging the formula to solve for mass gives m = F/a. Substituting the given values (F = 20 N, a = 4 m/s^2) gives m = 20 N / 4 m/s^2 = 5 kg.

Question 17

At a speed of 12 m/sec how far can you travel in one minute?
A) 12 m
B) 72 m
C) 60 m
D) 720 m

Accepted Answer

At a speed of 12 meters per second, in one minute (which is 60 seconds), you would travel 12 m/sec * 60 sec = 720 meters.

Question 18

Consider a 6 kg box of holiday candy on a horizontal surface such as a table. There is a 10N applied force to the right and a 7 N frictional force to the left. Suppose the block moves 3 m to the right across the table, to its impending doom of hungry guests.
-Please calculate the work done by the 10 N force.

Accepted Answer

The answer of Consider a 6 kg box of holiday...

Question 19

Consider a 6 kg box of holiday candy on a horizontal surface such as a table. There is a 10N applied force to the right and a 7 N frictional force to the left. Suppose the block moves 3 m to the right across the table, to its impending doom of hungry guests.
-What is the work done by the 7 N frictional force?

Accepted Answer

The answer of Consider a 6 kg box of holiday...

Question 20

Is it possible for the magnitude of an object's average velocity to be greater than its average speed? How about average speed being greater than the magnitude of the average velocity? Please explain.

Accepted Answer

The answer of Is it possible for the magnitude of...

Quiz 1: The Laws of Motion, Part 1

Suppose you have two cars, and the larger one is twice as massive as the smaller one. If you and a friend push on them so that their accelerations are equal, how must the forces applied to the cars compare?

Which of the following devices on a car can be used to cause the car to accelerate?

The acceleration of an object is equal to

Suppose you are at a stop light and realize that an important antique physics textbook sale ends in five minutes. Naturally, you start off very rapidly. To you, some papers on the dashboard fly straight backwards. To an observer on the ground they

The SI units of acceleration are

Suppose you have a car traveling down the road at constant speed and not changing direction. It is experiencing gravity, wind resistance and frictional forces from the road. What can be said about the car's acceleration?

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

If you are backing up but slowing down, your acceleration is directed

Under what conditions are the values of average speed and the magnitude of the average velocity equal?

You are making a round trip from City A to City B and back to City A again at constant speed. At what point in the trip is your average speed equal to three times the magnitude of your average velocity?

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.

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.

You walk in a given direction for 20 m during the first 5 seconds of a trip and then 15 m during the next 2 seconds. Your average speed is equal to

To cause a 25 kg object to experience an acceleration of 2 m/s2 the net force that needs to be applied to the object is

A net force of 8 N is applied to a 2 kg object. The object's acceleration is

An object experiences a net force of 20 N and has an acceleration of 4 m/s2. The object's mass must be

At a speed of 12 m/sec how far can you travel in one minute?

Is it possible for the magnitude of an object's average velocity to be greater than its average speed? How about average speed being greater than the magnitude of the average velocity? Please explain.

To cause a 25 kg object to experience an acceleration of 2 m/s² the net force that needs to be applied to the object is

An object experiences a net force of 20 N and has an acceleration of 4 m/s². The object's mass must be