1. Unbalanced Forces and Motion
What happens when multiple forces act on the same object?

2. Net Force
Net Force is the difference of two or more forces acting upon an object.
1000 N
2000 N
Force from paddling
Current from river

3. Unbalanced Force
Unbalanced Forces happen when two unequal forces act on each other.
Unbalanced forces set objects in motion.
100 N
Force of Gravity
Net Force 500 N up.
600 N
Force from kickers leg.

4. Balanced Force
Balanced Forces are two equal forces that cancel each other out.
Balanced forces cause a net force of zero.
Net Force Zero happens when two equal forces cancel each other out.
The force of gravity pulls the vase towards the ground.
30 N
Net Force Zero
30 N
The force of friction from the table pushes up against
the vase canceling out the force of gravity.

5. Which way will the objects move?
400 N
Example 1
Example 2
Example 3
2000 N
220 N
220 N
200 N
140 N

6. Which Object Will Move Faster?
500 N
Wind
5 N
Kick
30 N
Wind
20 N
Kick
40 N
Wind 40 N
600 N
Engine 1990 N
Wind 60 N
Engine 2000 N

7. Questions You May See On The EOG?
What are forces that have a net force of zero called? A. balanced B. unbalanced C. equal D. accelerating
What type of forces allows you to stand up from a chair? A. balanced B. equal C. unbalanced D. opposite
A ball has two forces acting on it. One force is pushing it to the left, and a larger force is pushing it to the right. In which direction will the ball move? A. right B. left C. up D. down