Summary Notes: Motion, Speed & Acceleration Vocabulary

Vocabulary flashcards covering fundamental definitions, types of motion, scalar vs. vector quantities, speed, velocity, momentum, acceleration, and graphical analysis.

Rest

The state of an object when it does not change its position over time.

Motion

The state of an object when it changes its position over time compared to a reference point.

Reference Point

A point or object used as a comparison to determine whether another object is in motion.

Linear Motion

Motion in a straight path, such as an apple falling straight down.

Curvilinear Motion

Motion in a curved path, such as a rollercoaster going over a hill.

Circular Motion

Motion around a circular path, such as the Earth orbiting the Sun.

Rotational Motion

Motion around an object's axis, such as the Earth spinning on its axis.

Oscillatory Motion

Motion moving back and forth, such as a clock pendulum.

Scalar Quantity

A quantity that has magnitude (size) only and no direction, such as mass, temperature, or speed.

Vector Quantity

A quantity that has both magnitude (size) and direction, such as force, velocity, or acceleration.

Distance

The total length of the path an object travels, which is a scalar quantity measured in meters ($\text{m}$).

Displacement

The shortest length between an object's start point and endpoint, which is a vector quantity that includes direction.

Speed

The distance an object travels in a unit of time, calculated as $s = \frac{d}{t}$ and measured in $\text{m/s}$.

Average Speed

Speed calculated by dividing total distance by total time ($s_{\text{avg}} = \frac{d_{\text{total}}}{t_{\text{total}}}$).

Instantaneous Speed

The speed of an object measured at an exact moment in time.

Constant Speed

Speed that is not changing over time.

Distance-Time Graph Slope

On a distance-time ($\text{D-T}$) graph, the slope represents the speed of the object.

Velocity

A vector measurement that includes both the speed of an object and its direction.

Momentum

A vector property calculated as mass times velocity ($p = m \times v$), measured in $\text{kg} \cdot \text{m/s}$.

Acceleration

The rate of change of an object's velocity over time, calculated as $a = \frac{v_f - v_i}{t}$ and measured in $\text{m/s}^2$.

Positive Acceleration

Acceleration that occurs when speed increases, such as a car accelerating at a green light.

Negative Acceleration

Acceleration that occurs when speed decreases, such as a car slowing down at a red light.

Centripetal Acceleration

Acceleration that occurs when an object changes its direction of motion, such as a car turning a corner.

Zero Acceleration

The state of motion when an object's speed and direction do not change at all.

Speed-Time Graph Slope

On a speed-time ($\text{S-T}$) graph, the slope represents the acceleration of the object.