Types of Forces

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.

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.

Applied Force

• A push or pull applied by a person or an object.

Normal Force

• The supportive force when one thing rests on another thing.• Squishy force.• Pillow force.

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.

Air Resistance Force

• The force that occurs when particles of air hit a moving object, making it harder to move.

Spring Force

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

Tension Force

• A pulling force in a string, rope, chain, or other similar material.

• Bridges have lots of tension forces.

Contact Forces

• Applied

• Air Resistance

• Frictional

• Normal

• Spring

• Tension

Action at a Distance Forces

• Gravitational

• Electric

• Magnetic

*** We learned about these forces in 8th Science Unit 1