Stage 5 Science Complete Study Guide

Vocabulary flashcards covering wave properties, kinematic quantities, Newton's laws of motion, terminal velocity mechanisms, and scientific experimental design parameters.

Wave

A periodic disturbance that transfers energy from one location to another through a medium or space without transporting physical matter.

Mechanical Waves

Waves that require a physical medium (solid, liquid, or gas) to travel (e.g., sound, water, seismic waves).

Electromagnetic Waves

Waves that do not require a medium and can propagate through a vacuum at the speed of light ($3 \times 10^8\,\text{m/s}$).

Transverse Waves

Waves in which particle displacement is perpendicular ($90\text{ degrees}$) to the direction of wave propagation.

Longitudinal Waves

Waves in which particle displacement is parallel to the direction of wave propagation.

Crests

The highest points of a transverse wave.

Troughs

The lowest points of a transverse wave.

Compressions

High density and pressure regions in a longitudinal wave.

Rarefactions

Low density and pressure regions in a longitudinal wave.

Amplitude (A)

The maximum displacement of a particle from its rest position, which relates directly to wave energy.

Wavelength ($\lambda$)

The distance between two consecutive in-phase points (e.g., crest to crest), measured in meters ($\text{m}$).

Frequency (f)

The number of complete wave cycles passing a fixed point per second, measured in Hertz ($\text{Hz}$).

Period (T)

The time taken for one complete wave cycle to pass a point, measured in seconds ($\text{s}$). Calculated as $T = \frac{1}{f}$.

Wave Velocity (v)

The speed at which energy travels through a medium, measured in $\text{m/s}$. Calculated as $v = f \times \lambda$.

Scalar Quantity

A physical quantity that has magnitude without direction (e.g., distance, speed, mass, time).

Vector Quantity

A physical quantity that has magnitude with an associated direction (e.g., displacement, velocity, acceleration, force).

Distance (s)

The total path length covered by a moving object.

Displacement

The straight-line distance from an initial position to a final position, including direction.

Average Speed ($v_{\text{avg}}$)

The rate of change of distance over time, calculated as $\text{Average Speed} = \frac{\text{distance}}{\text{time}}$.

Average Velocity ($v_{\text{avg}}$)

The rate of change of displacement over time, calculated as $\text{Average Velocity} = \frac{\text{displacement}}{\text{time}}$.

Acceleration (a)

The rate of change of velocity over time, measured in $\text{m/s}^2$. Calculated as $a = \frac{v - u}{t}$.

Newton's First Law (Inertia)

The law stating that an object remains at rest or continues to move at a constant velocity unless acted upon by a net external force ($F_{\text{net}}$).

Newton's Second Law

The law stating that acceleration is directly proportional to net force and inversely proportional to mass ($F_{\text{net}} = m \times a$).

Newton's Third Law (Action-Reaction)

The law stating that when one object exerts a force on a second object, the second object simultaneously exerts an equal and opposite force on the first ($\text{Force A on B} = -\text{Force B on A}$).

Weight (W)

The downward force due to gravity, calculated as $W = m \times g$ (where $g \approx 9.8\,\text{m/s}^2$ on Earth).

Air Resistance ($F_{\text{drag}}$)

The frictional force of air opposing motion, which increases as speed increases.

Terminal Velocity

The constant maximum velocity achieved when upward air resistance ($F_{\text{drag}}$) equals downward weight ($W$), resulting in zero net force ($F_{\text{net}} = 0\,\text{N}$) and zero acceleration ($a = 0\,\text{m/s}^2$).

Independent Variable (IV)

The variable that is deliberately changed in an experiment (e.g., height from which a balloon is dropped).

Dependent Variable (DV)

The variable that is measured in an experiment (e.g., time to reach the ground or calculated average speed).

Controlled Variables (CV)

Variables kept constant during an experiment to ensure a fair test (e.g., balloon shape/volume, attached mass, air currents).

Reliability

The consistency across repeated experimental trials, which is improved by running multiple trials per height and taking a mean.

Accuracy

The closeness of measurements to true values, which is improved using calibrated tools and slow-motion video.

Validity

The extent to which an experiment strictly measures what it claims, achieved by keeping all controlled variables constant so only the IV affects the DV.

Scientific Models

Physical or mathematical representations used to simulate complex real-world systems safely and cost-effectively.