Physics: Vectors, Scalars, Motion, and Newton's Laws

Vocabulary practice flashcards generated from lecture notes covering physics fundamentals including vectors, scalars, equations of motion, Newton's laws, and terminal velocity.

Vector

A physical quantity that has both magnitude and direction, such as velocity, displacement, force, acceleration, and weight.

Scalar

A physical quantity that has magnitude ONLY, such as speed, distance, mass, time, and energy.

Distance

The total length of the journey travelled by an object.

Displacement

A vector quantity defined as how far and in what direction an object is from its starting point.

Average Speed

The speed calculated over long time intervals using the relationship $d = v \times t$.

Instantaneous Speed

The speed of an object measured over a very short time interval, such as when a light gate measures the time taken for a card or mask to break a beam.

Balanced Forces

Equal and opposite forces acting on an object, resulting in a net force of zero.

Unbalanced Forces

Unequal forces acting on an object that cause it to accelerate.

Mass

The amount of matter in an object, measured in kilograms ($kg$).

Weight

The force acting on an object caused by a gravitational field pulling on it, measured in newtons ($N$) and calculated using $W = mg$.

Gravitational Field Strength

The gravitational force acting per unit mass, represented by $g$ and measured in $N\,kg^{-1}$.

Newton's First Law

An object at rest will remain at rest, and an object in motion will remain in motion at a constant velocity, unless acted upon by an unbalanced force.

Newton's Second Law

The acceleration of an object depends on the unbalanced force applied to it and its mass, defined by the formula $F = ma$.

Newton's Third Law

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

Free Fall

The state of motion where gravity is the only force acting upon an object, causing acceleration due to gravity.

Terminal Velocity

The constant, maximum speed a falling object reaches when the downward force of gravity is balanced by upward forces such as drag or air resistance, resulting in zero net force.

Acceleration

The rate of change of velocity over time, measured in $m\,s^{-2}$ and calculated using $a = \frac{v - u}{t}$, where $v$ is final velocity and $u$ is initial velocity.