Newton's Laws of Motion

Flashcards covering the vocabulary and core principles of Isaac Newton's three laws of motion and states of equilibrium.

Motion

The change in position of an object over time.

Force

A push or a pull on an object that can start, stop, or change motion.

newton ($N$)

The SI unit of force.

Balanced Forces

Equal forces acting in opposite directions that result in no change in motion.

Unbalanced Forces

Forces that cause motion to change.

Newton’s First Law (Law of Inertia)

An object at rest stays at rest, and an object in motion stays in motion unless acted upon by an unbalanced force.

Inertia

The resistance to change in motion; the greater the mass, the greater the inertia.

Equilibrium

The condition where there is no change in state of motion of an object and the net force acting is zero.

Net force

The combined effect of all individual pushes and pulls acting on an object.

$$\sum F = 0$$

The mathematical representation of equilibrium where the sum of all forces equals zero.

Translational Equilibrium

A state where an object moves in a straight line at constant speed without speeding up or slowing down.

Rotational Equilibrium

A state where an object is not speeding up or slowing down in its rotation, having no angular acceleration.

Static Equilibrium

A state where an object is completely still and balanced.

Dynamic Equilibrium

A state where an object is moving at constant velocity with no acceleration.

Newton’s Second Law (Law of Acceleration)

States that the acceleration of an object depends on the force and the mass, expressed by the formula $F = ma$.

Newton’s Third Law (Action & Reaction)

For every action, there is an equal and opposite reaction, meaning forces always occur in pairs.

$$F_{\text{action}} = -F_{\text{reaction}}$$

The mathematical expression for Newton's Third Law where the negative sign indicates forces are equal in magnitude but opposite in direction.