1. Inertia, Motion and Forces
Why are seat belts a good idea?
Inertia, Motion and Forces

2. What forces act upon this person during a car accident?

3. A force is a push or a pull
What is force?
           A force is a push or a pull
It can change the movement of an object
Sometimes forces are obvious, but not always.  Do you notice the force of the floor on your feet pushing you up?
Can you feel the force of the atmosphere pushing at your body?

4. Balanced Forces = forces that are equal in size and in opposite directions   (no movement occurs)

5. Unbalanced = the two forces are not equal, so that there is a movement in one direction.  
Net force = the combined forces acting on an object 
Examine this tug of war.  Each person can pull with exactly (1) force.  
What is the force for the team on the left side?  ____ What is the force for the team on the right side?  ____
What is the net force acting on the rope?  _____

6. What is INERTIA?
the tendency of an object in motion to remain in motion. 
You're riding in a car and the driver slams on the break suddenly, what happens to your body?  
What happens when you're standing on a bus and the bus starts to move?

7. 1. What is the first rule of physics. 2
1. What is the first rule of physics? 2. What would happen if you kicked the pebble in space? 3. Things like to keep on doing ___________________ 4. What is the latin word for “laziness”? ____________

8. Sir Issac Newton - developed the laws of motion
First Law of Motion    (also known as Inertia)
 - an object moving  will keep moving
- if an object is at rest, it will stay at rest
 - unless acted on by an unbalanced force

9. Jenga is a game based on inertia
Jenga is a game based on inertia.  You try to move the blocks without moving the other blocks. Eventually, the tower becomes unbalanced. 

10. According to Newton, why did the chicken cross the road?
All of the words relate to motion and forces. 

11. Answers
inertia
newton
motion
force
balanced
velocity
acceleration
speed
distance

12. QUIZ  TIME  -   FORCES

13. 1.  Objects in motion tend to _______________________
2.  Who developed the laws of motion? _____________
3.  The combined forces acting on an object is the ____ force.
4.  What is the physics word for LAZINESS?  __________
5.  Define force.  _______________________________