1. Types of Forces

2. Force is…
A force is a push or a pull resulting from an interaction between objects.
Since you can’t push or pull without doing so in a direction…force is a vector. It has a direction.
The unit for force is Newton.

3. Gravitational Force
The pulling force between two objects that have mass.
ALL objects that have mass are gravitationally attracted to each other.
The force of gravity is equal to the weight of an object.

4. Applied Force
A push or pull applied by a person or an object.

5. Normal Force
The supportive force when one thing rests on another thing.
Squishy force.
Pillow force.

6. Frictional Force
The force that opposes motion when moving (sliding friction) or still (static friction).
Different surfaces cause different amounts of frictional forces.
Friction causes heat.

7. Air Resistance Force
The force that occurs when particles of air hit a moving object, making it harder to move.

8. Spring Force
The force applied to a stretched or compressed spring wanting to return to it’s regular position.

9. Tension Force
A pulling force in a string, rope, chain, or other similar material.
Bridges have lots of tension forces.

10. Contact Forces
Applied
Air Resistance
Frictional
Normal
Spring
Tension

11. Action at a Distance Forces
Gravitational
Electric
Magnetic
*** We learned about these forces in 8th Science Unit 1