Any influence that tends to accelerate an object; a push or pull; measured in newtons. A vector quantity.
The force that acts to resist the relative motion (or attempted motion) of objects or materials that are in contact
The reluctance of any body to change its state of motion. Mass is the measure of this.
The fundamental SI unit of mass.
Every body continues in its state of rest, or of motion in a straight line at constant speed, unless it is compelled to change that state by a net force exerted upon it.
law of inertia
Newton's first law
A measure of an object's inertia; also a measure of the amount of matter in an object. Depends only on the amount of and kind of particles that compose an object—not on its location.
The combination of all the forces that act on an object.
SI unit of force.
For an object resting on a horizontal surface, the upward force that balances the weight of the object.
Force that completely balances the weight of an object at rest.
The force on a body due to the gravitational attraction of another body (commonly the earth).
Friction, or drag, that acts on something moving through air.
Anything that flows; in particular, any liquid or gas
When two values change in opposite directions.
The acceleration produced by a net force on a body is directly proportional to the magnitude of the net force, is in the same direction as the net force, and is inversely proportional to the mass of the body.
Newton's second law.
The SI unit of pressure.
The speed at which the acceleration of a falling object is zero because friction balances the weight.
Terminal speed together with the direction of motion (down for falling objects).
One of the pair of forces described in Newton's third law.
A mutual action between objects where each objects exerts an equal and opposite force on the other.
Whenever one body exerts a force on a second body, the second body exerts an equal and opposite force on the first.
Newton's third law
The force that is equal in strength and opposite in direction to the action force, and one that acts simultaneously on whatever is exerting the action force.