Jaime’s mishap with the bus

Newton law lab

Essential Question

• How do we describe what happens in a collision in terms of Newton’s Laws of Motion

Hand out Jaime’s Mishap with Bus

• Yellow pamphlet

• Name

• Class Period

• Read, answer the questions on page 14

Read story

• Describe what was happening with the bus and the car before the crash

• Why did the crash occur?

Question 1 (pg 14)

• Describe (using words or pictures) what forces acted on Jaime’s body during the collision?

P14 in yellow book

• Describe the forces pushing/pulling on Jaime’s during collision.

• Draw a free-body diagram

Free Body Diagram of Jaime

Upward force of seat

Weight

Friction and seat beltForward force of seat

P14

• Why is she having x-rays and an EKG

• What is the use of an X-ray?

• What is the use of an EKG?

EKG?

• electrocardiograph (ECG or EKG)

• Detects changes with the heart rate

• Primarily used to determine if the Heart has been damaged

X-rays, EKG tests

• X-rays

• See if there is any internal damage to bones

• MRI – see if there is any damage to soft tissues

• EKG

• See if there is any thing wrong with the heart, or circulation

Use of X-rays

Use of EKG

• Echocardiograms

MRI

• Magnetic Resonance Imagery

What are the factors that determine how fast a car comes

to a stop?

Some Factors that determine rate at which a car stops

• Road conditions

• Tire condition

• Brake Conditions

• Weather

• How distracted the driver is

• How tired the driver is

• If the driver is under the influence

What of the previous factors are influenced by the driver?

Driver influenced conditions

• Condition of the car

• Condition of the driver

• Rate at which the car moves

How close should you to another vehicle on the road?

How far apart should vehicles be driving down the road?

The rules

• The 2 second rule

• The 1 car length for every 10 mph rule

Crash Simulation #1

• Make a prediction:

• What do you think will happen to the clay passenger in the car when the bus crashes into its rear bumper. Specifically Predict the motion of the head, torso, hands and feet the instant after impact

Procedure

• Form Groups

• Each group will need to make the person in the car and the heads of the people on the bus

• Perform experiment as indicated

• Make observations

• Answer questions in book on pg 15-16

Car Crash Lab

• Each person is responsible for completionof pages 15-22

Write the predictions

BEFORE

Do and record the observations

Then

Answer any questions in book

Task #1

• Create and record motion of body/head on car

Task #2

• Create, record motion of the heads on bus

Warning

• Any horseplay or making of inappropriate anatomical parts for the clay figures will result in you spending the rest of the time in room 240 today and a zero for the missing pages of work

Group Selection

• 3-5 people per group

• My choice

Materials that need to be acquired by each group

• Ramp• Wooden Car• Clay• Scissors• 3-4 straws• 4-6 world history textbooks (by back window)• Ribbon (pick up from teacher when needed

• Same on the floor for ramp, start ramp from a seat

Run

• Make observations on head, neck, body, (hands and feet)

Make sense of your observations:

• What parts of the body were at rest before the collision?

• Did these parts of the body try to stay at rest after the collision? Explain your answer

How does 1st law of motion connect to what you saw?

Questions #3 and 4

#3 Although you observed the bus striking the car, where did the actual push acting on clay passenger come from?

#4 What is the common name used for neck injuries sustained in a rear end collision

Part B, Passengers on the Bus

• Predict what will happen to the heads and necks of the passengers on the bus the instant after impact?

Mark down observations

• Head

• Neck

Does 1st law explain your observations?

Sim II Who needs a seatbelt?

• Use 1st law to predict what would happen to the passenger when his car crashes into a fixed barrier w/o seatbelt?

• What part of the car causes the most deaths in a head on collision w/o seatbelts?

Observations

• Head, Neck, Body

Making sense

• What is the force that pulled the car and passenger down ramp?

• Describe motion of passenger: Acc, CV

Making Sense #3

• A) what was force that caused motion of car to abruptly change?

• Balanced or unbalanced forces on car at time of accident?

Making Sense #3

• B) Describe resulting motion of car when it struck barrier: Acc, CV

• C) Explain motion of passenger using 1st law

If Fluffy the Kitty was sleeping (without a seatbelt) in the rear

window well …Describe Fluffy’s motion if the car

was involved in a head-on collision?

Crash Sim III Seat belts types

• Pre Lab discussion

Investigating the effect of seatbelt width

• Can seat belts be too wide? Too narrow?

Pressure (force per area) is important concern

Other features of seatbelts

• Why not make seat belts out of metal?

• Why not make seat belts out of leather?

• Can seat belts be too wide? Too narrow?

Pressure (force per area) is important concern

Other features of seatbelts

• Why not make seat belts out of metal?

• Why not make seat belts out of leather?

Use 1st law of motion to explain the benefits of using a shoulder

harness

Page 21

Create a free body diagram of each car to answer questions 1 and 2

Predict the relative amount of force of the car and bus

Pg 21

• What do you think happened to the students on the bus?

• Injuries? Types?

• Motion of students at time of impact?

Bottom of page 21

Compare the car’s force on the bus to the force the bus applies to the car

Are they the same size?

Are they applied in the same direction?

Are they applied at the same time?

Pg 22

Situation #1How does force that one student exerts on the other

compare?

Situation #2How does force of car on tree compare to force of

tree on car?

Situation #3How does the forces exerted by the bus and car on

each other compare?

Pg 22

Situation #1

2 students (one larger, taller than other)Neither is moving

How does force that one student exerts on the other compare?

Draw free-body diagrams on each

Pg 22

Situation #2

Wooden car crashing into a barrier and comes to a stop

How does force of car on tree compare to force of tree on car?

Draw free body diagrams of each.

Pg 22

• Objects in motion

• School bus crashes into Jaime’s car

• How does the forces exerted by the bus and car on each other compare?

• Draw free body diagrams of each

Comparison of action-reaction forces in different situations

Make predictions for each situations on page 23-25

Comparing forces in contact

• Two people leaning against each other

Neither is moving

How do the forces each exerts on the other compare?

Sit #2 Fast moving object crashing into stationary object

• What are the action and reaction forces?

• How do they compare?

Objects in motion

• What are the action and reaction forces?

• How do they compare?

Compare forces between objects

• Pg 23-25

For each situation:

F1 = the force that person 1 applies to person 2

F2 = the force that person 2 applies to person 1

P27

• Write the third law in the scroll

• Answer the question below the scroll

P29

• On the moon, the acceleration due to gravity is 1.7m/s2

• Complete part 1 and part 2

• Inertia is measured by mass

P30

• Finding the weight of an object

• Weight = ___________ x ___________

• Weight = mass X acceleration due to gravity

Complete part IV on page 30

Homework in Yellow Book

• Page 35-37 problems 3-8

Thursday

• Go over 29, 30, 35-37

• Finish the yellow book

• Seat-belts debate

• Seat-belt assignment

• Grades and hand-back tests ?

To answer questions

• Circle the relationship you think is true

• Answer #4 on pg 24

• Answer #3 and #4 on pg 25

Newton’s Third Law

• For every action force, there is an equal reaction force applies in the opposite direction

Third law

• Every force is matched with a equal sized reaction force

• Action and reaction force are NOT applied to the same object

• Action and reaction force are applied at the same time

Scale Demo

• Push your scale gently against the other scale (no more than 60)

• Have one person hold firm and the other person do the pushing

• Have both people moving while pushing

Who was injured more severely, the kids on the bus or

Jamie?Why?

Reason

• Both bus and car exerted the same force on each other

• Amount of force changes the motion of the car much more, due to the difference in mass

• The Mass of the object

• That is why the bus is less effected by the crash than the car…it has more mass!

NOT because there was less force applied to it

Who needs seatbelts?

• Safety features of cars

• Safety features of buses

Fill out page 45 in yellow book

Sum up• How do the forces exerted on the car and bus from the collision

compare?

• How does the mass of the car compare to the mass of the bus?

• Which object (Bus, Car) will accelerate more because of the applied force from the accident?

• How can the motion of the students on the bus be related to the 1st and 3rd law?

• Knowing about action-reaction forces, why was there more damage done to the car?

Seat Belts

• Did Jaime’s seatbelt help or harm her?

• Would seatbelts have helped or harmed the students on the bus for this accident?

• Are there other types of accidents with school buses that would have changed your answer in the above question?

The Seatbelt issue

• Read pg 46-51 (includes some articles on the issue of seat-belts on buses

• Answer the first 3 questions on page 46

• Use the internet to see if any district or states requires school buses to have seatbelts– get specifics

• Determine if other buses are required to have seatbelts (greyhound…)

Seatbelt Position Paper

• Decide for yourself whether there should be a law that mandates that all school buses have seatbelts for each student.

• One-two pages Typewritten, (handwritten will lose points)

• Provide some evidence for both sides of the argument. Indicate the source of the evidence in the paper

• Use the laws of Newton correctly to back up evidence• Bring up other issues (Security, cost…) in addition to

help argue your position• Grammar, Paragraph structure will count as well as

strength of argument, evidence

RubricSeat belt paper (50 points) Friday

• Up to nine points each for:– At least 3 worthwhile reasons for seatbelts– At least 3 worthwhile reasons against belts– Connection between each law to seatbelts

• Up to six points each for:– Clear statement of position on seatbelts– How well the project written– Condition of project

• Up to 4 points for:– references from outside articles or other sources

Can you think of Bus accidents where seat belts would be

useful?

Do you believe that school buses should have seatbelts?

• Reasons for mandatory seatbelts

• Reasons against seatbelts

Ideas

• For seatbelts • Against seatbelts

Safety on school bus report

• Read pg 46 and the 3 articles on the following pages.

• Seek out at least one other source of information that will help you answer the first 3 questions on page 46.

• Write a position paper on whether schools should be forces to put seatbelts on all buses

Report should:

• Be typed• 1-2 pages• Cite at least 4 sources• Indicate your position in the opening paragraph• Include at least 3 reasons for seatbelts• Include at least 3 reasons against seatbelts• A final paragraph that indicates the reason(s)

that determined your choice, be persuasive• Bibliography• Use the laws of motion in explanation of reasons

Discussion

How does speed relate to force?

Does it matter the size of the vehicles that crash together?

http://upload.wikimedia.org/wikipedia/en/7/7e/Img0a36.jpg

Do you need seatbelts on a bus?

• Write a paper listing at least 3 reasons for having seat belts and 3 reasons for not having seat belts.

• Connect all of Newton’s laws to support your reasons

• Determine your answer to the above questions

• Turn in to me on Tuesday of next week