1. March 20, Happy Spring!
Homework: Complete Will, Bill, and Phil worksheet- Read over Fig. 3 on page. 39 in textbook
Do Now: -Write down homework, put worksheet in notebook- glue in later
Update T.O.C: pg: 1: The nature of Force, pg 2: Combining Forces: Net Force/ Unbalanced Forces
Open Textbook to pg. 36- Open NB. To pg 89/1

2. Chapter 2- Forces The Big Idea: Motion and Forces
Essential Question (EQ):
What causes an objects motion to change?

3. Force The nature of force
Where does it all begin?
What causes an object to start moving, stop moving or change direction?
Force
-Is a push or a pull- exerted by one object onto a second object.
-Force is described by its strength and direction
and these are symbolized with an arrow

5. The strength and direction a can be represented with an arrow
Points in the direction of the force
The length of the arrow shows its strength.
**The longer the arrow the greater the force**

6. The Newton (N)
The strength of a force is measured in the SI unit called a newton (N)
One newton of force = lifting up a small lemon

7. Net Force/ (un)Balanced Forces
Net Force – the combination of all the forces acting on an object-Determines if the object moves and which direction it moves in- It always acts in the direction of the greatest force.
Unbalanced force:-} Can cause an object to start moving, stop moving or change direction- results in a net force and causes a change in motion
Balanced Forces:-} Equal forces acting on one object in opposite directions- there is no change in motion and no net force

8. Tug-of-war?
If the net force is anything other than zero (0)- forces are unbalanced and there is a change in motion

9. Combining forces( pg. 2 in Notebook)
Look at Fig. 2 on pg. 37:
When the two arrows are going in the same direction they are added together to find the net force
Two forces act in opposite directions- they are subtracted (or like adding a positive # to a Negative #)
*The net force ALWAYS acts in the direction of the greatest force.*
A net force of zero (0) --the forces are balanced- no change in motion
Strength and direction of individual forces determines the net force:

10. Is the force Balanced or unbalanced?
What is the net force and in which direction is it going in?