1. On your next blank page, take notes Force Notes

2. Net Force In many situations, including driving, more than one force is acting on an object. The combination of all forces acting on an object is the net force. Net force determines whether, and by how much, an objects motion is changed. Total Force

3. Force Diagrams Objects are shown as a rectangle or square.

4. Force Diagrams A push or pull (force) is shown with an arrow

5. Force Diagrams The arrow always points AWAY from the object.

6. Force Diagrams The bigger the force, the bigger the arrow

7. Force Diagrams Label the arrows with the magnitude (amount) of the force (in N) 10 N 3 N

8. Force Diagrams Net Force is the sum of all of the forces 10 N3 N 7 N

9. Practice: Draw an object with two forces acting in opposite directions with one force equal to 2 N and one force equal to 8 N.

10. Force Diagrams 8 N 2 N

11. Net Force Draw the net force acting on this object. 8 N 2 N

12. Force Diagrams Net Force 6 N

13. Balanced vs. Unbalanced Forces If there is a situation of unbalanced forces, there is a net force. Balanced forces mean there is a net force of zero on the object. Describe the motion of the blocks below. 10 N 2 N 8 N A. B.

14. Read pg. E-37

15. Activity 81 Title: The Net Force Challenge Problem: How can you tell if the forces on an object are balanced or unbalanced? Hypothesis: If _____________, then ______________________________.

16. Read the procedure on pages E-38 to E-39

17. Data/Evidence: Part A: Balanced Forces Step 3. Part B: Unbalanced Forces Step 6. Step 7. Etc.

18. Spring Scale BE GENTLE!!!!