1. Make an OEQ in your notebook, and leave lots of space for questions!
I Fly Ballet video

2. Everything on Earth falls at the same rate of acceleration regardless of Mass
Prove me wrong!
Can you come up with times things don’t fall at the same rate of acceleration?

3. Galileo discovered that heavy objects fall at the same rate of acceleration as light objects!
Mass doesn’t matter! They hit the ground at the same time!

4. What is a vacuum?
A VACUUM is a space where almost all the atoms have been removed!

5. What did you see? Why did this happen?
Bowling Ball Feather Video

6. What is Friction? Talk to the person next to you.

7. In your notebook, title a page “Friction investigation”
Include a section for Observations
Include a section for Rules for Friction
Include a section for Class results

8. Play with the Friction box and use the spring scales to construct rules that describe:
How does Friction work?
What causes Friction?
What is the effect of friction on force required to change motion?

9. Graffiti Splash: Write the rules you have constructed on the board
Each group use a different color
Be prepared to back up your rule with evidence!

10. Friction Notes

11. What causes Friction?
Friction is caused by Electric and Static Forces- the forces of attraction between atoms
All matter is made of positive and negative charges, so there is always some attraction between atoms. When a force pulls matter away from each other, they RESIST the change, because of the attraction between atoms.
Friction is a force that acts in the opposite direction of motion.

12. a

13. Force Diagrams: diagrams to show the direction and strength of all forces acting on an object.

14. Drawing Force diagrams: Boat in water

15. Car on the road:

16. Draw a model of the effect of friction on your white board
Draw a model of the effect of friction on your white board. Be prepared to share
Table 1: Swimmer moving in water
Table 2: Ball rolling across the ground
Table 3: Airplane in the air
Table 4: Meteorite falling through the atmosphere
Table 5: Person walking
Table 6: Tug of war contest

17. Adding Forces:
If a ball is rolling forward with a force of 20 N and the friction force between the ball and the ground is 5 N. What force does the ball have overall?

18. Net force: the sum of all forces acting on an object
The force of friction is subtracted from the force of the ball to give the NET FORCE.
20 N (F ball) – 5 N (F friction) = 15 N of NET FORCE.
We use the word NET any time two opposing values are combined to give the overall amount.
Gross income – taxes = NET income = this is the actual amount you have to spend (what’s left over after taxes)
Net force = the measured force of motion (what’s left over after friction)

19. What is terminal velocity?
Terminal Velocity: when an object falls at a constant speed and no longer accelerates because gravitational force and friction forces are balanced