Science (Sound) - 1st Periodical Examination

Sound

A sensation that stimulates the ears.

Ears

The organs for hearing.

Pleasant Sounds

Sounds pleasant to the ears.

Noise

Sounds unpleasant to the ears.

Sound Energy

An energy produced by a vibrating body.

Resonance

The quality or condition wherein vibrations or waves are prolonged by an external force or by another vibration.

Echo

The reflection of sound when it bounces back from a hard surface.

Reverberation

A series of echoes.

Frequency

The number of vibrations of a sound per unit of time.

Hertz

Vibrations per second.

Pitch

The highness or lowness of a tone.

20 Hz to 20 000 Hz

The number of Hertz humans can hear.

Wavelength

The horizontal distance from one crest of a wave to another or from one trough to another.

Crest

The highest part of a wave.

Through

The lowest part of a wave.

2 cm to 17 m

The length of a wavelength humans can hear.

Amplitude

The measure of the amount of energy of a sound wave.

Intensity

The magnitude of sound energy as it travels through a unit area.

Volume

The loudness or the softness of a sound.

Decibel

Intensity or volume's measurement.

Alexander Graham Bell

The inventor of the telephone.

0 dB

Threshold of Hearing

140 dB

Threshold of Pain

Power

The measure of sound energy per unit of time.

Quality

The fullness and richness of a sound.

344 m/s

Average speed of sound.

Solid

Matter where particles are compact and closely arranged next to one another.

Liquid

Matter where particles are slightly apart.

Gas

Matter where particles are widely dispersed.

Salinity

The measure of amount of salt dissolved in liquids.

Humidity

The amount of moisture in air.