Sound and Light Vocabulary

Beat

Periodic and Repeating fluctuations heard in the intensity of a sound waves of very similar frequencies interfere with one another.
Can be caused at antinodes.

Consonance

A combination of two different pleasant pitches.

Constructive Interference

This is caused by superposition of waves with displacements in the same direction that amplify each other.

Decibel

The unit of measurement for sound.

Destructive Interference

This is caused by the superposition of waves with opposite amplitude that cancel each other out.

Dissonance

An unpleasant set of pitches.

Doppler Effect

The apparent change in frequency of a wave caused by the relative motion between the wave's source and the observer.
EX: Ambulance

Doppler Shift

a change in frequency due to the Doppler effect.

Illuminated Source

An object that becomes visible as a result of the light reflecting off it.
EX: Moon

Interference

...

Longitudinal Wave

Parallel to the direction of motion of the wave.
EX: Sound

Luminous Flux

The rate at which light energy is emitted form a luminous source.

Luminous Source

An object that emits light.
EX: Sun

Opaque

A material that transmits no incident light

Polarized

...

Ray Model of Light

Light in which is represented as a ray that travels in a straight path, the direction of which can be changed only by placing an obstruction in the path.

Sound Wave

A pressure variation that is transmitted through matter is a sound wave.

Translucent

A material transmits light, but objects can't be seen clearly
through it.

Transparent

A material that transmits light clearly

Wave

Any rhythmic disturbance that carries energy through matter or space.

Wave Pulse

A single bump or disturbance that travels through a medium.

Frequency

Number of oscillations in pressure each second

Wavelenght

the distance between successive regions of high or low pressure

The speed of sound in air depends on

Temperature

Active Sonar

acoustic signal sent out and sound bounces back if objects are in the path of the waves

Passive Sonar

A receiver used to listen to sound made by vessels and marine life

Amplitude

The measure of the variation in pressure along a wave

Loudness, depends primarily on the ______ of the pressure wave

Amplitude

Light can also be studied using the ______ model or the _____ model

wave, particle

Illuminance

the rate at which light strikes the surface

Light Year

the distance that light can travel in one year. 9.62 x 10^12

Visible Light is a form of _____

EM Radiation