Unit 01 “Forces and the Laws of

Motion”How to Answer Questions

about Newton’s Laws

Constructing Proficient ResponsesA.E.S. 3-Steps to Constructing a Proficient

Response

1.Answer the question.In a complete sentence answer the question with a “yes” or a “no” or by stating the results.

2.Explain the Relationship or Law.State the Law or fundamental concept that explains the situation.Explain the relationship between the variables. (If one changes, does the other change?)

3.Support with Data and/or Observations.Give specific data (numbers) that prove the relationship is validGive specific observations to prove the law or concept is valid

Constructing Proficient Responses…with Newton’s Laws

1. Answer the question.– What happened or what will happen?

2. Explain the relationship.– Which Newton’s law explains the answer: 1st 2nd 3rd?

3. Support with data/observations.– How does the law explain answer …• what observations demonstrate the law? • what numerical data demonstrate the law?

Question 1:When a truck with a ball in the bed accelerates forward, does

the ball roll backwards?

When a truck with a ball in the bed accelerates forward, does the ball roll backwards?

To answer the question, think about what happen …

First …• What was at rest?

• The truck and the basketball. • Both the truck and the ball were not moving at first.

After …• What moved?

• The truck moved.

• What didn’t move?• The basketball didn’t move.• Newton’s 1st law says that an object at rest will stay at

rest unless a force is put on it.• There was no force on the ball, so the ball doesn’t

move.

Then…• What had a force on it?

• The truck had a force on it.

• What didn’t have a force on it?• The basketball didn’t have a force on it, nothing

pushed or pulled the ball.

When a truck with a ball in the bed accelerates forward, does the ball roll backwards?

1. Answer the Question.

• No, the basketball didn’t roll backwards, it stayed at rest.2. Explain the Relationship.

• According the Newton’s 1st Law, an object at rest stays at rest unless acted on by an outside force.

3. Support with Data/Observations.

• The truck had an outside force on it, so it moved forward. • The ball didn’t have an outside force on it so it continued

to stay at rest.• The truck moved from under the ball, so it looked like the

ball rolled backwards.

Two Skaters push against each other with an equal and opposite force. Which skater will accelerate more,

the larger or smaller skater?

Question 2:

Two Skaters push against each other with an equal and opposite force.

Which skater will accelerate more, the larger or smaller skater?

In Class DemoSkater Force (F)

NMass (m)

kgAcceleration (a)

m/s2

1 200 80 2.52 200 40 5

Volunteers Please!

Observations? The bigger skater doesn’t move as far.

The smaller skater moves more!

So … the bigger skater has LESS acceleration …The smaller skater has MORE!!!

2nd Law! Mass and Acceleration are inversely proportional when the same force is applied!

Two Skaters push against each other with an equal and opposite force.

Which skater will accelerate more, the larger or smaller skater?

?1.Answer the Question.2.Explain the Relationship.3.Support with Data/Observations.

1. Answer the Question.

• The smaller skater will accelerate more.2. Explain the Relationship.

• According to Newton’s 2nd Law mass and acceleration are inversely proportional. [The more mass the less acceleration and the less mass the more acceleration.]

3. Support with Data/Observations.

• For example, the skater with a large mass of 80kg had a small acceleration of 2.5m/s2.

• While the skater with a small mass of 40kg had a bigger acceleration of 5m/s2.

Two Skaters push against each other with an equal and opposite force.

Which skater will accelerate more, the larger or smaller skater?

If a student hits Ms Bucci’s face with

their hand, can the student say that Ms Bucci hit them

back?

Question 3:

Orbis used Physics and Newton’s 3rd Law to get

Ms Bucci Fired….

Orbis told Mr. Sutherland that Ms Bucci hit him.

If a student hits Ms Bucci’s face with their hand, can the student say that Ms

Bucci hit them back?

Afterschool Orbis punches Ms Bucci…

I hate you,

Ms Bucci!Owwwww! My face!

(and my heart!)

Later… Ms Bucci is called to Mr. Sutherland’s office.

Umm… did I?

Ms Bucci … did you hit a

student!!!!?????

Ms Bucci remembers ….

Hmmm…Newton’s 3rd Law says for every force there is

an equal and opposite force …

Action: Orbis’ hand pushed my face.

Reaction: My face pushed Orbis’ hand.

Oh no!!! That means if Orbis hit me, I

did hit him back!OH NO!!!

… the truth is …

Yes, according to Newton’s 3rd Law, I did hit a student!

Then you are

FIRED!!!!

NO!!!

If a student hits Ms Bucci’s face with their hand, can the student

say that Ms Bucci hit them back? 1. Answer the Question.

• Yes, the student can say that Ms Bucci hit them back!2. Explain the Relationship.

• According to Newton’s 3rd Law, for every force applied to an object (action), the object applies an equal and opposite force back (reaction).

3. Support with Data/Observations.

• The action was the student’s hand pushed Ms Bucci’s face.

• So the reaction was Ms Bucci’s face pushed the student’s hand back!

• So she technically hit the student!

Practice A.E.S.

• Practice answer questions completely using the three A.E.S. steps!

• Good luck!

A girl at a roller rink was trying to skate so she “pushed herself off the table” to begin moving backwards. Why is it wrong to say “she pushed herself off the table”?

A girl at a roller rink was trying to skate so she “pushed herself off the table” to begin moving backwards. Why is it wrong to say “she pushed herself off the table”?• It is wrong to say “she pushed herself off the table”

because she pushed the table, not herself.• According to Newton’s 3rd Law, for every force

applied to an object the object applies an equal and opposite force back.

• In this case the girl pushed the table and the table pushed her back. This is why she moved.

Look at the data table below. What factor affects the acceleration of an object?

Object Force (F) N

Mass (m)kg

Acceleration (a)m/s2

Round Ball 100 50 2Box 100 15 7

Rubber Ducky 100 4 25

Look at the data table below. What factor affects the acceleration of an object?

• The mass of the object affects it’s acceleration.• According to Newton’s 2nd Law mass and

acceleration are inversely proportional.• The object with greater mass of 50kg had the

smallest acceleration of 2m/s2. While the object with the smallest mass of 4kg had the greatest acceleration 25m/s2.

A truck is driving with passengers in the bed of the truck. When the truck stops quickly do the people “fly out” because they get pushed forward?

A truck is driving with passengers in the bed of the truck. When the truck stops quickly do the people “fly out” because they get pushed forward?• No, the people do not get pushed forward.• According to Newton’s 1st law, an object in constant

velocity motion will stay in constant velocity motion unless acted on by an outside force.

• The truck and the people were moving but only the truck had a force on it, so it stopped. There was no force on the people so they CONTINUED to move forward … they were not pushed forward.