Sound Notes Sound Sound is created by a

Sound Notes

Sound • • Sound is created by a vibration It is a mechanical wave(longitudinal) Requires a medium DEMO

Speed of Sound • Speed of sound is dependent on the: • Medium –the more dense the medium the _______ • Temperature-the higher the temp the ______. About. 6 m/s per degree increase • Altitude – the higher the altitude the _____ • 343 m/s super sonic

Frequency • Number of vibrations per second • It is a quanitative value measured in ____

Pitch • It is a qualitative value • It is directly related to frequency • Hi Freq= Hi pitch/Low freq=Low pitch

Loudness • Loudness can be qualitative value or It can be quanitative • It is directly related to amplitude

Amplitude • Amplitude is the amount of energy in a wave • It is directly related to loudness

Decibels • The units to measure loudness of a sound quanitatively • It is a log scale • What is a Decibel?

Decibels

Resonance • Ability of an object to vibrate at its natural frequency • http: //www. youtube. com/watch? v=3 mclp 9 Qm. C Gs • https: //www. youtube. com/watch? v=Ude 8 p. Pjaw KI • https: //www. youtube. com/watch? v=0 K 8 zs-KSitc watch to the 2: 20 mark of this one • https: //www. youtube. com/watch? v=od. Jx. JRAxd. F U

Resonance • Ability of an object to vibrate at its natural frequency • Hair Trick

Reflection • It is the bouncing back of a wave. In sound it is an____.

Echolocation • The use of sound to locate objects • Some species of animals use it to locate prey ex. bats, dolphins • https: //www. youtube. com/watch? v =Z_E 3 zxx 2 l 9 g

SONAR • Acronym that represents Sound Navigation and Ranging • Used to detect objects underwater • New technology used in WWII • What is SONAR

Ultrasound • A sound greater than 20, 000 Hz • Used in medicines to diagnose disease • Humans can only detect sounds from 20 Hz-20, 000 Hz • Tone Generator and Beat

Interference • Constructive – consonance – a pleasant set of pitches • Destructive – dissonance – an unpleasant set of pitches • Interference waves

Beat • Oscillation of wave amplitude that occurs as a result of the superposition of two sound waves having nearly identical frequencies. • Tone Generator and Beat

Octave • Two musical notes with frequencies related by a 1: 2 ratio.

Doppler Effect/ Shift • An apparent change in sound frequency due to relative motion of either the source or the detector. • Ex. – radar gun, astronomy, meteorology, train, sirens…