8th Grade STAAR Review: Category 2- Force, Motion and Energy

A push or a pull

• Gravity

• Friction

• Force

• Inertia

Any force that resists motion

• Inertia

• Force

• Gravity

• Friction

An object's tendency to stay at rest or keep moving; depends on mass.

• Inertia

• Friction

• Gravity

• Force

An always-present force of attraction between all masses in the universe.

• Gravity

• Inertia

• Force

• Friction

When all forces acting on an object are equal (net force is zero), so it does not cause a change in motion. It will continue in a straight line and a constant speed.

• Balanced Force

• Unbalanced Force

• Friction

• Gravity

When all forces acting on an object are not equal; causes a change in motion. It will accelerate (speed up, slow down, change direction).

• Balanced Force

• Unbalanced Force

• Inertia

• Gravity

Speed and Direction

• Speed

• Velocity

• Acceleration

A change in speed, direction or both. (Speed up, slow down or change direction).

• Speed

• Velocity

• Acceleration

Speed = Distance divided by Time

• Speed

• Velocity

• Acceleration

The hurricane is moving Northwest at 20km/h

• Speed

• Velocity

• Acceleration