Balanced and Unbalanced Forces

1. Balanced and Unbalanced Forces 9/14/18 https://www.youtube.com/watch?v=QMpYOW8fpl8

2. What is a FORCE? • A force is a push or pull that can cause motion (speed up, slow down, stop, move, or change direction) • Force is measured in Newtons (N) • Force is measured using a spring scale https://www.youtube.com/watch?v=B6mi1-YoRT4

3. 2 Common Forces Gravity: force of attraction between two objects, Earth’s gravity pulls on all objects Friction: a force that resists motion between two surfaces that are pressed together Net Force – The overall force

4. Balanced Force Equal forces in opposite directions produce no motion

5. Balanced Forces • When forces are balanced there is either: 1. No motion Ex: stopped car at a stop sign 2. Constant Motion Ex: setting your car on cruise control Object is already moving

6. Balanced Forces • Balanced forces do not cause a change in motion. • The forces are equal. 10 N 10 N 10 N – 10 N = 0 N

7. Unbalanced Forces Unequal opposing forces produce an unbalanced force causing motion

8. Unbalanced Forces • When forces are unbalanced there is a change in motion. 1. Moving in same directionadd forces together to get the net force. 2. Moving in opposite directions subtractthe forces to get the net force.

9. Unbalanced Forces • The forces are NOT equal. 20 N 10 N 20 N – 10 N = 10 N 8 N 6 N 8 N + 6 N = 14 N

10. Unbalanced Forces 3 N, right – 6 N, left = 3N, left

11. Unbalanced Forces 4 N, left – 10 N, right = 6N, right https://www.youtube.com/watch?v=L_TXu8ih668

12. Unbalanced Forces 5 N, right + 10 N, right = 15N, right

13. Net Force • Net Force -The overall Force acting on an object • Expressed in Newtons (N) https://www.youtube.com/watch?v=qQi667U_Mig

14. NET FORCE • Add (Right) = • Add (Left) = • Subtract = • Subtract = Help each other Going same direction ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬ Oppose each other Go against

15. LET’S PRACTICE! https://www.youtube.com/watch?v=YwpT0ZBxcys

16. Balanced vs Unbalanced On the earthquake Releasing energy of the Fault line 2 Women lifting a box into the back of a truck U U 2 people pulling opposite directions on a rope with the same amount of force A moon that orbits A planets B B A skier going Down a mountain A book sitting high on A bookshelf U B

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19. Calculating NET FORCE Net Force= 17N Net Force= 50 N Net Force= 7 N Net Force= 40 N Net Force= 50 N