Forces Unit vocabulary

Force

Force

a push or pull on an object

Net force

The combination of all forces acting on an object

Balanced force

Equal forces acting on an object in opposite directions, there is no change in motion

Unbalanced force

two or more forces that are not equal and opposite of one another; can cause change in motion

Motion

An object's change in position relative to a reference point.

Speed

The distance an object travels per unit of time

Velocity

the speed of an object in a particular direction

Newton

SI unit of force, equal to 100g on earth

Friction

A force that opposes motion between two surfaces that are in contact

Gravity

A force of attraction between objects that is due to their masses, a distance force

Mass

the amount of matter in an object

Weight

A measure of the force of gravity on an object

Projectile motion

the curved path that an object follows when thrown, launched, or otherwise projected near the surface of Earth, has horizontal and vertical motion

Energy

The ability to do work or cause change

Energy transfer

The conversion of one form of energy into another, or the movement of energy from one place to another.

Kinetic energy

the energy an object has due to its motion

Potential energy

stored energy that results from the position or shape of an object

Horizontal force

A force that acts in a direction parallel with the horizon

Vertical force

A force that acts in a direction perpendicular to the horizon

Counteract

to act in opposition to

Dynamic friction

Friction that acts due to movement of one surface over another

Static friction

Friction that acts on objects that are not moving

Stationary

standing still; not moving

Acceleration

rate of change of velocity, change in speed or direction

Deceleration

negative acceleration

Newton's first law of motion

An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

Newton's Second Law

Force = mass x acceleration

Newton's Third Law

For every action force there is an equal and opposite reaction force