Frictional Forces (Casey Hayes)

Title: Friction forces against Hotwheels.

Principle(s) Investigated: Newtons 3rd Law, friction, and gravity.

Standards

MS-PS2-2

Plan an investigation to provide evidence that the change in an object’s motion depends on the sum of the forces on the object and the mass of the object. [Clarification Statement: Emphasis is on balanced (Newton’s First Law) and unbalanced forces in a system, qualitative comparisons of forces, mass and changes in motion (Newton’s Second Law), frame of reference, and specification of units.] [Assessment Boundary: Assessment is limited to forces and changes in motion in one-dimension in an inertial reference frame and to change in one variable at a time. Assessment does not include the use of trigonometry.]

Materials:

• 2 Textbooks
• Tape
• Hot Wheel Car
• Hot Wheels Track
• Towel
• T-Shirt
• Foam
• Felt
• Sandpaper
• Measuring Tape, or meter stick.

Procedure:

1. Make hypothesis for materials. How will each each compare?
2. Stack the two textbooks and tape the hot wheels track to the very edge of the top book.
3. Put the car's back wheels at the top of the track and release it.
4. Record the distances of each car on each material 3 times. Record average on Google Sheet
5. Take average scores and enter them into google sheet for each material.

Student prior knowledge:

• The students must be familiar with forces and interactions of an object in motion.
• Students must know how to construct a hypothesis and plan investigation of forces.

Explanation: Students will be able to visually examine the different forces acting on a car. By using a fixed position and ramp, we can get more accurate data for each material. The distance that the car travels on each trial will be related to the amount of friction. Once data is entered in the Google Sheet, we can view the class data as a whole and we can decipher other variables in the experiment.

Questions & Answers:

1. What differences do you see between the different groups of cars? why?
2. What variables changed that changed the total distance traveled by the car?
3. What would happen if the car was heavier?

Applications to Everyday Life: This can be translated to real world examples where forces of friction are acting on cars. These examples can also be used to explain other areas where friction is more or less advantageous. An example could be a train that rides on steel with low rolling resistance which is an advantage.

Photographs: Coming soon

Videos: https://www.youtube.com/watch?v=CTLXubXOTUQ

https://www.youtube.com/watch?v=TDVhk6SB8VA

https://www.youtube.com/watch?v=c2bO20DFcpA

https://www.youtube.com/watch?v=YoxbplnG2FQ