SCIENCE 9 FIRST SUMMATIVE

3 LAWS OF MOTION

3 laws of motion

Law of Inertia, Law of Acceleration, Law of Interaction

Force

A push or pull on an object

Balanced Forces

Equal in magnitude and opposite in direction

Unbalanced Forces

not equal in magnitude or are not acting in opposite directions.

Motion

The change in the position of an object over time relative to a reference point.

Inertia

A tendency of an object to resist changes in its velocity (acceleration).

“An object will continue to be in the state of rest or in a state of motion unless an unbalanced force acts on it.”

Law of Inertia

Contact Forces

objects are in direct physical contact

Non-Contact Forces

without requiring direct physical contact between objects.

Vector Quantity

Has both magnitude and direction

Newton

1 kg = 9.8N

Mass

Amount of matter

Weight

Force of gravity

Net Force

Sum of all forces

Acceleration (m/s2)

The rate at which an object's velocity changes over time.

Acceleration only happens when there is a net force.

An object with more mass accelerates faster if you push it with the same force.

Weight and Mass are the exact same thing in physics.

Law of Acceleration

Greater force produces greater acceleration, greater mass produces smaller Acceleration is same force is applied.

Free fall

The motion of an object when gravity is the only force acting on it.

Air Resistance

The force exerted by air that opposes the motion of a moving object.

Terminal Velocity

Air resistance balances the force of gravity.

Interaction

A mutual action between two objects where each object exerts a force on the other.

Action Force

The force exerted by one object on another object during an interaction.

Reaction Force

The force exerted back by the second object on the first object.

Law of Interaction

For every action, there is an equal and opposite reaction.