Chapter

Section 1:

Learning Objectives:
  • Evaluate your understanding of safety
  • Identify and evaluate safety features in selected automobiles
  • Compare and contrast the safety features in selected automobiles
  • Identify safety features required for other models of transportation (in-line skates, skateboards, bicycles)

Investigate

1. True
False
False
False
False
False
False
True
False
True
False
False
False
True
True

Physics to Go

1.
seat belts- FRST
turn signals- FRST
front airbags- F
front crumple zone- F
back crumple zone- R
side airbags- S
side impact beams on doors- S
anti-lock braking system- F
energy-absorbing collapsible steering wheel- F
2.
helmets
knee pads
elbow pads
3.
helmet
knee pads
elbow pads
4.
helmet
knee pads
elbow pads
5.
something for the people in the back in an accident
double shoulder seat belts

6.
They feel very comfortable in their cars

Section 2

What do you see?
  • the dummy in the second car is ejected from the car
  • the dummy in the first car stays in the car
  • the first car has more damage than the second car

Investigate

2
a. Low speed- the guy flips out of the car and lands on the table
3
a. High speed- In the high speed collision the guy doesn't go as far as I thought he would. It wasn't as bad as I had expected
Part B
2
a. 9 and 1/4th inches
3
a. thin wire- the guy didn't fly out of the car but the seat belt dug into his body in several spots
thick wire- he stayed in the car, but the wire dug into his body in a few spots
ribbon- he stayed in place and the ribbon didn't do any damage to his body
b. The thin wire dug into his body in a few places and so did the thicker wire. Overall the best was the ribbon
4
a. The chest depressed 5cm and the whole body went forward
b. The head, chest, and torso

Physics Talk

  • There are 3 collisions within one accident
  • Newton's first law of motion can explain these three collisions when an automobile strikes a pole
      • First collision- The automobile strikes the pole. The pole exerts the force that brings the automobile to rest
      • Second collision- When the automobile stops, the body keeps moving. The structure of the automobile exerts the force that brings the organs to rest
      • Third collision- The body stops, but the heart, brain, and other organs keep moving. The body wall exerts the force that brings the organs to rest
  • force- an interaction between two objects that can result in an acceleration of either or both objects
  • pressure- force per area where the force is normal(perpendicular) to the surface; measured in N/m^2
    • force that is spread out over a given area

Checking Up

  1. An object at rest will stay at rest and an object in motion will stay in motion unless acted on by a force
  2. Because your body is going at the same speed as the car and when the body jerks forward all of the organs inside go forward as well
  3. First collision- The automobile strikes the pole. The pole exerts the force that brings the automobile to rest. Second collision- When the automobile stops, the body keeps moving. The structure of the automobile exerts the force that brings the organs to rest Third collision- The body stops, but the heart, brain, and other organs keep moving. The body wall exerts the force that brings the organs to rest
  4. Inertia- the natural tendency of an object to remain at rest or to remain moving with constant speed in a straight line
  5. It covered more of the body and the thin wire dug into the clay person's body.

Physics To Go

1.
a. A vehicle in motion will stay in motion until an object acts against it.
b.
c. Your body and things in the car are going at the same speed as the car. When you make a stop the things in the car and your body jerk forward because they don't stop as fast
d. The seat belt keeps the passenger in the same spot and keeps them inside of the car
2. An automobile strikes a pole, and the pole exerts a force that brings the automobile to rest OR A person who is running with ear buds, when they stop running the ear buds fall out because they want to keep going at the speed the person is going
b.
3.
4. First collision- The automobile strikes the pole. The pole exerts the force that brings the automobile to rest. Second collision- When the automobile stops, the body keeps moving. The structure of the automobile exerts the force that brings the organs to rest Third collision- The body stops, but the heart, brain, and other organs keep moving. The body wall exerts the force that brings the organs to rest
5. A wire seat belt would not be strong enough and could possibly hurt the person, a thicker one covers more surface area
6. I do think that seat belt laws are fair. They are put in place to help keep you safe in case of a bad car accident.
7.
a. "We aren't going far", "They are irritating"
b. They keep you in the car in case of a bad car accident where you could be ejected from the car.
8. Your head jerks forward but your brain wants to stay in the same spot
9. 2.8cm

Section 3

What do you see?
  • two cars crashed into each other
  • the person in the red car smashed his face into the air bag
  • the red guy has his seat belt on, the person in the green car doesn't
What do you think?
  • the airbag takes away some of the force in the crash making it not as severe on the body

Investigate

3a. 4cm
4a. smashed at 24cm
5a. We dropped him from the same height and some of the rice came out of the dish, but he didn't crack
6a. 2.5cm
7a. From 24cm there is no damage to egg #2 because the rice broke its fall. Egg #2 finally broke at 70cm.

Section 5

Investigate

2a. The blue car kept going forward even after the red car hit it. The blue car went all the way off of the track
3.
a. The red car hit he blue car and the blue car went faster than it did before.
b. This time the red car continued to move after it hit the blue car
c. When two cars are driving and they get into a rear end collision
4.
a. The blue car with the extra weight went a lot slower and didn't go as far as without the weights
5.
a. the red car has a weight and takes longer to slow down
b. a larger car hitting a smaller car
c. no because it weighs less than the larger cart

Section 6

Investigate

Mass of Object 1 (blue)
Mass of Object 2 (red)
Velocity of Object 1 before Collision
Velocity of Object 2 before Collision
Mass of Combined Objects Before Collision
Velocity of Combined Objects After Collision
.256
.256
.5
0
.512
.22
.744
.744
.167
0
.1488
.095
1.005
1.005
.55
0
2.01
.21



0



Momentum of object 1
Momentum of Object 2
Momentum of Combined Objects