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University of Nebraska–Lincoln

Transportation Systems Engineering

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Lesson Overview
Lesson Title:
May the forces be with you!

Mr. Mark Shearer (Primary)

Brief Description:
This lesson develops Newton's third law and impulse/momentum as it applies to crash wall tests.

Topics Introduced:
Civil Engineering

Transportation, Distribution, and Logistics Curriculum Framework Components Addressed:
Health, Safety and Environmental Management
Suggested Grade Levels:
11th Grade
12th Grade

Standards Taught:
12.2.1 Science 2003
12.6.1 Science 2003
12.3.4 Science 2003

Lesson Information
Learning Expectations:

The student will gain an understanding of Newton's 3 rd law and the c

concept of impulse/momentum.

The student will then apply these ideas to Motorsport Safety

Research involving Guardrail systems.

Plan Of Action:

1. Begin by developing the concept of a force.  Use standard definitions from any physics text book and students responses.
2. Give examples of contact and long range forces.  (i.e. contact forces, where 2 bodies physically touch and long range examples would be gravitational, electrical, and magnetic.)
3. Identify Action / Reaction pairs. (i.e.  A bat hitting a ball.  The action force would be the bat hitting the ball and the reaction, the ball hitting the bat.)
4. Ask, "What is the magnitude of these forces? (action/reaction pairs)
5. Demo: Using the track, cars and sensors, collide the two carts and change variables like velocity, mass, angle.(i.e. standard ones used in physics such as, 2 cars with the same mass and velocity coming towards each other.) Use the demo sheet here.
6. Reach conclusion that the forces are equal and opposite.
7. State/define Newton's 3rd law.
8. Give other examples of 3rd law and other demos. (i.e. such as a gun recoil, bug hitting a windshield on the interstate.)
9. Now develop the concept of momentum and impulse. No need at this point to quantify. Allow flexibility of the individual instructor to develop these terms in ways familiar to them.
10. Now apply all concepts to guardrail design. How can we increase the time to decrease the force?  Apply to the crash wall in auto racing.
11. Show videos of crash tests and show UNL's rail design.  These videos can be obtained from UNL transportation Systems Engineering, 402-472-1974.
12.  At this time, the instructor may add anything else they would like to on these topics and then proctor the exam.

Data Set Used:

No previous data set will be needed. Data will be generated during the lesson.

Materials Needed:

Preparation for this lesson will involve getting out equipment for the demonstration. Pasco or Vernier dynamics track and two carts.

Two wireless or wired sensors.

Software from Vernier called, "Physics with computers".

Various masses.

3rd law demos.

Preparation Period:

Preparation for this lesson will involve getting out equipment for the demonstration. Get out a Pasco or Vernier dynamics track and two carts. Attach two wireless or wired sensors to each cart.

You will need software from Vernier called, "Physics with computers". Use file 11, or Newton's 3rd law.

Also have some masses handy to add to the cart to change variables.

I also get out any 3rd law demos to add in concept development.

Implementation Period:

This lesson can be implemented in appoximately one 45-50 minute period.

Science, Math, Engineering and / or Technology Implications:

Understanding the science concepts or knowledge will lead students to apply this information to engineering design in reducing injury in guardrail collisions.

Unexpected Results:

Unexpected results usually occur with the technology portion of this lesson.  For example, the sensors may not communicate to the computer via blue tooth.  THe wireless sensors didn't get charged.

The power and strength of the lesson depends on the software and sensors to show that the forces are equal and opposite.  The lesson may have limited application in some schools due to lack of equipment.  If the school is at least able to get the software and sensors, they could substitute the cart/track system with anything they have in the department.  It does have to be vernier or pasco carts and track.  However it is convenient to use carts with equal mass.

No key is provided to the test.  The intent or reason for this is, its assumed the teacher will have sufficent knowledge in this area to make one. This is common practice in non text book curriculums.

Considerations for Diversity in Education:

This lesson will access multiple modalities and Intelligences such as visual, auditory, kinestic, and spatial.


Lesson Files
Demo sheet
Use this to record information concerning collisions. ( will the force be the same or different) Also draw pictures of your collisions.
[size: 27136] [date uploaded: Jul 17, 2008, 9:05 pm ]

08_U9 test -1 .doc
Momentum exam
[size: 32256] [date uploaded: Jul 17, 2008, 9:08 pm ]

Instruction Sheet
This is an instruction sheet for the lesson.
[size: 734720] [date uploaded: Mar 31, 2011, 10:29 am ]

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