Forces & Motion CA Review 1

We are learning to: explain motion We are looking for: an act, process, or instance of changing position through time. 2

We are learning to: explain the difference between speed and velocity We are looking for: Speed = change in distance/ change in time. Velocity = speed + direction of an object. Velocity has a direction, while speed does not. 3

We are learning to: explain the difference between speed and velocity and interpret graphs. We are looking for: Speed = change in distance/ change in time. Velocity = speed + direction of an object. Velocity has a direction, while speed does not. 4

We are learning to: explain how acceleration is a change in an object’s speed or direction We are looking for: the change in an object’s motion, which is caused by either speeding up, slowing down, or changing direction 5

We are learning to: explain balanced and unbalanced forces We are looking for: Balanced forces result in zero net for and no acceleration. Unbalanced forces result in acceleration of the object in the direction of the greater force We are learning to: explain how friction impacts the motion of an object We are looking for: friction opposes motion 6

We are learning to: explain how gravity affects the motion of an object. We are looking for: gravitational pull causes objects to accelerate. 7

We are learning to: explain Newton’s First Law of Motion We are looking for: an object in motion remains in motion; an object at rest remains at rest unless acted upon by an outside force 8

We are learning to: explain Newton’s Second Law of Motion We are looking for: how an unbalanced force causes an object to accelerate. 9

We are learning to: explain Newton’s Third Law of Motion We are looking for: every action there is an equal and opposite reaction (i.e. rocket launching) 10

Which of the following describes motion? A.A change in mass over time B.A change in position over mass C.A change in distance over time D.A change in mass over distance 11

How do you know that the car is in motion? A. The distance between the building and car changes. B. The time it takes the car to move is constant. C. The distance between the building and the car stays constant. 12

What is the SI or metric unit for distance? a)Miles b)Grams c)Meter d)Feet 13

What is used for comparison to tell if an object is in motion? a)direction b)reference point c)Speed d)velocity 14

What is the formula needed to calculate speed of an object? A.distance x time B.distance / time C.time / distance D.acceleration x time E.I need help! 15

Joe Shmoe walks 30 meters in 10 seconds. What was his speed? A.5 meters/second B.3 seconds/meter C.3 meters/second D.I need help! 16

What is the only difference between speed and velocity? A.Speed is more complex while velocity is less complex. B.Velocity is time divided by distance and speed is distance divided by time. C.Velocity requires a direction while speed does not. D.Speed and velocity are calculated differently. E.I need help! 17

Which of the following is an acceptable unit for velocity? A.Meters per second B.Feet per hour C.Miles per hour South D.Miles per hour E.I need help! 18

You are asked to create a graph that shows the speed of an object. What should be plotted on the x and y axes? A.Y axis = speed; X axis = time B.Y axis = time; X axis = distance C.Y axis = distance; X axis = time D.Y axis = time; X axis = acceleration 19

What is this graph showing? A.A person walking at varying speeds. B.A person walking at a constant speed and then stopping to rest. C.A person standing still. D.A person walked three miles. 20

What does this graph show? A.The object is not moving. B.The object is moving at a constant speed. C.The object is moving at a constant speed then stopped to rest. D.The object is moving at varying speeds. Distance 0 Time D 21

What does a steep slope of a line on a distance time graph indicate? A.Speed is fast B.Speed is slow C.The object is not moving D.Speed is changing 22

Which of the following is NOT an example of acceleration? A.Walking in a straight line at a constant speed B.Approaching a stop sign C.A ball rolling down a hill D.Turning around a corner at a constant speed 23

Which of the following best describes a decrease in speed? A.Positive Acceleration B.Negative Acceleration C.Constant velocity D.Average speed 24

Suzie is running around a track at a constant speed of 5 m/s. Why is she accelerating? A.She is running at a constant speed B.She is changing direction C.She is speeding up D.She is slowing down 25

What is plotted on the y-axis when graphing acceleration? A.Speed B.Time C.Distance D.Acceleration 26

Force is measured in units of… A.m/s B.Newtons C.m/s 2 D.grams 27

What is the net force? 40 N 30 N A.10 N to the left B.10 N to the right C.0 N D.10 N 28

What is the Net Force? 40 N A.10 N to the left B.10 N to the right C.0 N D.10 N 29

Which of the following arrows represents the force of friction? B A C D A.A B.B C.C D.D 30

Which one of the following forces opposes motion? a)gravity b)friction c)applied force d)centripetal force 31

Why does the Earth have more gravity than the moon? A.The moon revolves faster than the Earth B.The moon has less mass than the Earth C.Earth is a greater distance from the sun. D.The Earth has more water on it. E.I don’t know – I need help! 32

Ignoring air resistance, what object will hit the ground first when each is dropped from the same height? A.Baseball B.Bowling ball C.Both will hit at same time D.I don’t know- I need help! 33

Which statement best describes gravity? A.Gravity pushes objects towards Earth B.Gravity acts on all objects unless they are moving C.Gravity pulls objects towards Earth D.Gravity is as strong on Earth as on the moon E.I don’t know – I need help! 34

An object reaches its terminal velocity when… A.the force of gravity is greater B.the force of gravity and the force of air resistance are balanced C.the force of air resistance is greater D.I don’t know – I need help! 35

The tendency of an object to resist a change in motion is A.Gravity B.Friction C.Inertia D.Momentum E.I don’t know – I need help! 36

The greater the mass of an object… A.the lesser the gravity. B.the greater the inertia. C.the lesser the force. D.the lesser the inertia. E.I don’t know – I need help! 37

Which will have the greatest inertia? 1.Bowling ball 2.Baseball 3.Tennis Ball 4.Ping pong ball 5.I don’t know- I need help! 38

Your parent presses the car brakes while driving …which of the following describes your motion? A.Your body moves backward B.Your body does not move C.Your body moves forward D.Your body remains at rest E.I don’t know – I need help! 39

Newton’s Second Law states that… A.Objects in motion stay in motion. B.Objects at rest stay at rest. C.If a net force is applied onto an object, it will accelerate. D.For every action there is an equal and opposite reaction. E.I don’t know – I need help! 40

You are having difficulty pulling a pile of books in a wagon. What would be the best way to increase the acceleration of the wagon? A.Remove some books from the wagon. B.Add some books to the wagon. C.Remove the wheels from the wagon. D.Have a friend help you get on an exercise program E.I don’t know – I need help! 41

A person pushes a 10kg shopping cart down the isle. The cart accelerates at a rate of 2m/s 2. How much force did he exert on the cart? A.5 N B.12 N C.20 N D.5 kg E.I don’t know – I need help! 42

What will happen to this object if the forces are applied? 40 N 30 N A.The object will accelerate to the left. B.The object will accelerate to the right. C.The object will stay at rest. D.The object will not accelerate. E.I don’t know – I need help! 43

Which of the following situations best illustrates Newton’s Third Law of Motion? A.A boy pulling a wagon, which accelerates. B.Inflating a balloon and releasing it. C.Moving forward when a car stops. D.I don’t know – I need help! 44

Which of the following describes Newton’s Third Law of Motion? A.Objects at rest stay at rest. B.If you apply a net force, acceleration will occur. C.Objects in motion stay in motion. D.For every action there is an equal and opposite reaction. E.I don’t know – I need help! 45

A space shuttle is being launched. Identify the action force. A.Release of Gas B.Gravity C.Lift-Off D.Weight of Shuttle E.I don’t know- I need help! 46

How does Newton’s 3 rd Law apply to your ability to walk? A.Ground pushes down and your foot pushes up. B.Your foot pushes down with a greater force and the ground pushes back with a lesser force. C.Your foot pushes down on the ground and the ground pushes back with an equal force. D.I don’t know, I need help. 47