SOUND WAVESSOUND WAVES are the result of are the result of

VIBRATIONSVIBRATIONS

A A SOUND WAVESOUND WAVE is a is a LONGITUDINAL WAVE LONGITUDINAL WAVE but it but it is drawn as a transverse waveis drawn as a transverse wave

Since a sound wave consists of a repeating pattern of high pressure and low pressure regions moving through a medium, it is sometimes referred to as a pressure wave

Sound is a Sound is a MECHANICAL WAVEMECHANICAL WAVE

Sound requires a medium Sound can travel in a solid, liquid, or gas

The The SpeedSpeed of SOUND in AIR of SOUND in AIR

The speed of sound 331 m/s at 00C The speed of sound increases about 0.6 m/s for each

0C rise in temperature

Sound travels faster in liquids and fastest in solids than in air (a gas) because the molecules are closer together

vT = v0 + 0.6T

The The FrequencyFrequency of a SOUND WAVEof a SOUND WAVE

Represents the PITCH or a NOTE on a MUSICAL SCALE

Frequencies of SoundFrequencies of Sound The human ear is capable of detecting sound waves between

20 Hz to 20 000 Hz. Any sound with a frequency below the audible range of

hearing is an infrasound and any sound with a frequency above the audible range of hearing is known as an ultrasound.

Dogs can detect frequencies between 50 Hz and 45 000 Hz. Bats, who must rely on sound echolocation for navigation and

hunting, can detect frequencies as high as 120 000 Hz. Dolphins can detect frequencies as high as 200 000 Hz. An elephant possesses the unusual ability to detect

infrasound, having an audible range from approximately 5 Hz to approximately 10 000 Hz.

The The AMPLITUDEAMPLITUDE of a SOUND WAVEof a SOUND WAVE

Represents the LOUDNESS of the sound

LOUDNESS in DecibelsLOUDNESS in Decibels0 Silence

10 Heartbeat

20 Whisper

30 Soft piano

50 Soft talking

60 Conversation

80 Street traffic

90 Food blender

110 Thunder

120 Painful sounds

170 Jet engine

ResonanceResonance

Resonance occurs when two interconnected objects share the same frequency.

Resonance occurs when one object vibrating at the same natural frequency of a second object forces that second object to vibrate.

The Doppler EffectThe Doppler Effect

The Doppler EffectThe Doppler Effect