Chapter 4: Newton's Second Law of Motion

Question 1

The mass of an object

Answer 1

Is not a vector and has no direction

Question 2

Consider a car at rest, parked on level ground. The force of friction between a car tire and the ground

Answer 2

Is zero

Question 3

In order to state the force exerted on one object by another object you must give

Answer 3

Both the magnitude of the force and the direction of the force

Question 4

Under which circumstances is a force exerted on an apple by your hand?

Answer 4

When the apple is at rest in your open hand

Question 5

This is a measurement of an object’s inertia

Answer 5

Mass

Question 6

Which of the following is a valid force that could be exerted on a baseball?

Answer 6

The force on a baseball being hit by a bat

Question 7

Which of the following is a legitimate way to describe the force between a skydiver and the earth as the skydiver is falling toward the ground?

Answer 7

The force of gravity exerted by the Earth on the skydiver

Question 8

You are lying on your back on the slope of a grassy hill, watching the clouds go by overhead. Which of the best statement about the force of friction exerted on you by the ground in this situation?

Answer 8

A force of static friction pointing “up the hill” parallel to the surface of the hill, is applied to you by the ground

Question 9

Acceleration can be expressed in units of m/s^2 or

Answer 9

N/kg

Question 10

Which of the following statement is true about sliding friction?

Answer 10

Sliding friction is always in the direction that opposes motion

Question 11

The acceleration of an object during free fall depends on the

Answer 11

Amount of gravity

Question 12

In general, when a car is driving along a straight road, the force of friction between a car tire and the road

Answer 12

Can point either forward or backward, depending on what the car is doing

Question 13

If you know all of the forces acting on an object and you know the mass of that object, what quantities can you figure out from that information?

Answer 13

The acceleration of the object

Question 14

If you could somehow increase the mass of an object, what would happen to the net force on the object?

Answer 14

The net force on an object does not depend on the object’s mass

Question 15

Newtons and pounds are

Answer 15

Different units fro measuring forces

Question 16

Which of there is a valid force that could be exerted on a car racing through narrow city street?

Answer 16

The force of friction between the road and the car (its tires)

Question 17

Newtons and kilograms

Answer 17

Unit for different quantities, and cannot be converted to each other

Question 18

Under which circumstances, is there a force exerted on the apple by your hand?

Answer 18

When you are picking the apple up off the floor

Question 19

An object’s mass and weight are

Answer 19

Proportional to each other

Question 20

Forces can be expressed in units of

Answer 20

Newtons or pounds

Question 21

Two identical car are traveling down the road. Car A is traveling at 60 mph, and car B is traveling at 40 mph. Which car has more friction acting on it?

Answer 21

Neither, both cars have the same amount of friction

Question 22

When trying to analyze the forces in a situation we sometimes invent forces that don’t actually exist. Which of these force is Not a valid force that could be exerted on a sled being pulled along a snowy path by a girl?

Answer 22

The force of motion pushing the sled forward

Question 23

You are about to check out at the grocery store, and you put a box of cereal on the converyer belt at the register. The cashier turns on the conveyors belt, causing the box of cereal to speed up momentarily. At this moment, what can we say about the frictional force acting on the box of cereal?

Answer 23

There is a static frictional force pointing in the box’s direction of motion, parallel to the conveyor belt

Question 24

Which of the following is a legitimate way to describe the force between a skydiver and the air she is falling through as the skydiver

Answer 24

The drag force exerted by the air on the skydiver

Question 25

Under which circumstances, is a force exerted on an apple by your hand?

Answer 25

When the apple is at rest in your open hand