1. Chapter 10-3 Warm-Up
1. What are three factors that can change an object’s acceleration?
2. What units are used to measure speed? Acceleration?
3. What is the equation for acceleration?
4. What is happening in the graph (red line)?

2. Chapter
Motion and Force

3. Force
Force – a push or pull
Net force – a combination of all forces

4. Force Force Latin word “fortis” which means strength
Example - fortress

5. Forces Balanced Forces – Equal forces acting in the opposite direction
A. No movement occurs
Unbalanced Forces – Unequal forces acting in any direction
A. Movement occurs

7. Friction
Friction - A force that opposes motion between two surfaces that are in contact
“Hills and valley”

8. Static Friction
Static Friction – The force that resists the initiation of sliding motion between two surfaces that are in contact and at rest.
A. Requires the most amount of force

9. Kinetic friction
Kinetic Friction – The force that opposes the movement of two surfaces that are in contact and are sliding over each other.

10. Types of Friction
Sliding Friction – Objects slide past each other

11. Types of Friction
Rolling Friction – Object rolls over a surface

12. Types of Friction Fluid Friction - Object moves over a liquid or gas
Streamlining

13. Friction Harmful Friction – Reduce the amount of friction
A. Lubricant – Substances that reduce friction (oil, wax, grease)

14. Friction Helpful Friction – Need this friction to function
Sand on ice, tires on cars, feet and the ground
Hydroplaning