1. Force Notes Part 1

2. What is a Force? Examples:
When you ride a bike, your foot pushes against the pedal. The push makes the wheels of the bike move.
When you drop something, it is pulled to the ground by gravity.
A force is a push or pull in a particular direction.

3. What is a Force? Examples: Forces affect motion by making objects:
start moving
stop moving
move faster
move slower
change direction
change shape

4. How are forces depicted?
Every force has a specific strength
The SI unit for the strength of a force is the Newton (N)
1N of force is exerted when you lift a lemon

5. How are forces depicted?
Every force has a specific direction
Arrows are drawn in the direction the force acts in
Size of arrow reflects strength of force
Arrows are labeled with the strength of the force

6. Examples
Push
Right
Pull
Left
Pull
Down
Push
Left
Push
Down

7. How do forces interact? Forces rarely act alone
Multiple forces act on a single object in many directions.
Net Force = the combination of all forces acting on an object.

8. How do forces interact? Forces acting in the same direction:
Are added together
Result in an arrow facing the same direction. 4N 8N 4N

9. Example
Two students are working together to push a large box. Justine pushes the box to the right with 200N of force, while Brittany pushes the box to the right with 150N of force. Draw and label the net force.
200N
150N
Net Force
350N

10. How do forces interact? Forces acting in opposite directions:
Are subtracted together
Result in an arrow facing the direction of the greater force. 4N 8N 4N

11. Example
Brittany thinks she is stronger than Justine so she moves to the other side of the box and pushes in the opposite direction. Using the same forces above, draw the net force:
200N
150N
50N
Net Force

12. Example Find the net force of the forces shown below: 370N 360N 10N