Physics: Motion and Newton's Laws Vocabulary

Vocabulary flashcards covering key definitions, equations, units, and concepts from lecture notes on kinematics, free fall, and Newton's laws.

Speed

The rate of movement, defined as the time rate of change of distance from a reference point, calculated using the equation $\text{Speed} = \frac{\text{Distance}}{\text{Elapsed Time}}$.

Meters per second ($m/s$)

The standard SI unit used to measure speed and velocity.

Average Speed

The total distance traveled by an object divided by the total elapsed time.

Instantaneous Speed

The speed of an object measured at a specific single moment in time.

Velocity

A vector quantity that specifies how fast an object is moving as well as its direction of motion.

Constant Velocity

Motion in which an object maintains both an unchanging speed and an unchanging direction.

Acceleration

The rate at which velocity changes over time, occurring whenever speed or direction changes.

Average Acceleration Equation

The formula $\text{Average Acceleration} = \frac{\text{Final velocity} - \text{Initial velocity}}{\text{Time}}$, measured in SI units of $m/s^2$.

Impact Speed

The relative speed between two moving bodies at the moment they collide or make contact.

Free Fall

The motion of an object falling under the influence of gravity alone, with no other forces such as air resistance acting on it.

Free Fall Acceleration ($g$)

The constant downward acceleration of an object in free fall near Earth's surface, equal to $g = 9.8\,m/s^2$ (or approximately $10\,m/s^2$).

Free Fall Speed Equation

The formula $v = g \times t$ used to calculate the speed of an object dropped from rest after an elapsed time $t$.

Free Fall Distance Equation

The formula $d = \frac{1}{2}(g \times t^2)$ used to calculate how far an object dropped from rest falls in an elapsed time $t$.

Force

A push or a pull that can cause an object's shape to distort or cause a change in its velocity.

Newton ($N$)

The standard SI unit used to measure force.

Pound ($\text{lb}$)

An everyday unit used to measure force.

Vector Quantity

A physical quantity that possesses both a magnitude and a direction.

Newton's First Law

Also known as the Law of Inertia, describing the property where an object maintains its state of rest or uniform motion unless acted upon by a net force.

Inertia

The inherent resistance of any physical object to a change in its velocity or state of motion.

Zero Velocity Motion

The state of motion in which an object is completely at rest.