study guide com science

Newton's First Law of Motion

An object will remain in its state of motion unless acted upon by an unbalanced force.

Newton's Second Law of Motion

The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass, represented by the equation F = ma.

Newton's Third Law of Motion

When one object exerts a force on another object, the second object exerts an equal and opposite force back on the first object.

Sound Transmission Properties

Requires a medium with properties that support the propagation of vibrational energy, including elasticity, density, and temperature.

Solid State of Matter

Particles are tightly packed together, have a definite shape and volume, and vibrate in place without moving around.

Liquid State of Matter

Particles are loosely packed together, have a definite volume, but can change shape as they flow around each other.

Gas State of Matter

Particles move freely and spread apart, having no definite volume or shape.

Brownian Motion

The random movement of tiny particles caused by collisions with smaller molecules, contributing to the movement of sound waves.

Velocity

The speed and direction of an object’s motion; in sound, it refers to how fast a wave travels through a medium.

Force

A push or pull on an object that causes it to move, stop, or change direction.

Pressure in Sound Waves

The amount of force applied over an area, with changes creating compressions and rarefactions in a wave.

Wave

A repeating disturbance that moves through a medium, transferring energy without transporting matter.

Medium

The substance (air, water, solid) through which a wave travels.

Sound

Vibrations that travel as waves through a medium and can be heard when they reach the ear.

Psychoacoustics

The study of how humans perceive and interpret sound.

Frequency

The number of vibrations (cycles) per second in a sound wave, measured in Hertz (Hz).

Period (T)

The time it takes for one complete cycle of a wave to occur, measured in seconds (s).

Amplitude

The height of a sound wave, which determines its loudness, measured in decibels (dB).

Inertia

The tendency of an object to resist changes in motion.

Mass

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

Elasticity

A material’s ability to return to its original shape after being disturbed.

Compression (Condensation)

A region in a sound wave where air particles are pushed close together, creating an area of high pressure.

Rarefaction

A region in a sound wave where air particles are spread apart, creating an area of low pressure.

Transverse Wave

A wave where compressions correspond to the peaks and rarefactions correspond to the valleys.

Longitudinal Wave

A wave where compressions appear as dense particle regions and rarefactions appear as spaced-out regions.

Sound Propagation

The process of sound waves traveling through a medium, creating disturbances that transfer energy.

Inverse Square Law

Sound intensity decreases as the distance from the source increases; intensity is inversely proportional to the square of the distance.

Intensity and Amplitude Relationship

Higher amplitude results in greater intensity; doubling amplitude makes intensity four times greater.

Intensity and Frequency Relationship

Higher frequencies can carry more energy per cycle, but loudness primarily depends on amplitude.

Frequency and Period Relationship

They are inversely related; higher frequency = shorter period, lower frequency = longer period.

Sound Pressure vs dB SPL

Sound pressure measures the physical force of sound waves; dB SPL measures how loud that pressure is.

Dynamic Range of Auditory System

Range from 0 dB SPL (threshold of hearing) to 120-140 dB SPL (pain threshold).

Waveform Graph X-Axis

Represents time, showing how the wave changes over a period.

Waveform Graph Y-Axis

Represents amplitude, indicating the intensity or loudness of the wave.

Speed of Sound Factors

Medium’s density, temperature, and elasticity affect the speed of sound.

Pure Tone

A sound consisting of a single frequency, producing a sinusoidal waveform.

Complex Sound

A sound comprising multiple frequencies simultaneously, resulting in a richer audio experience.

Harmonic Series

A sequence of frequencies where each frequency is an integer multiple of a fundamental frequency.

Fundamental Frequency

The lowest frequency of a periodic waveform, determining the pitch of the sound.

Spectrum Plot

A graphical representation showing the frequencies present in a sound and their amplitudes.