Presentation on theme: "Name ___________________________________________ Date ________________ Period _________ P HYSICS P ART I – S URFING THE W AVES Wave Theory Waves transfer."— Presentation transcript:
Name ___________________________________________ Date ________________ Period _________ P HYSICS P ART I – S URFING THE W AVES Wave Theory Waves transfer ________ through a medium. The __________ doesn’t move – the energy does. Longitudinal Wave Wave Types Molecules move _________________________ as the wave. Transverse Wave Molecules move ________________ to the direction of the wave.
Actual Wave How we can think of it Wavelength – Amplitude = Pitch velocity = wavelength x frequency v = λ ƒ Velocity is constant As frequency increases, _____________________________. As wavelength increases, ____________________________.
Interference Standing Wave In a closed tube, the wave _________________________. Waves of a ________ frequency than the fundamental – add richness to tones. Different instruments accentuate different ____________. Overtones
Loudness Measured in __________ – indicate the amplitude of the wave. Source of soundSound pressure level Sound in airdB re 20 μPa Shockwave (distorted sound waves > 1 atm; waveform valleys are clipped at zero pressure)atm>194 dB Theoretical limit for undistorted sound at 1 atmosphere environmental pressure~ dB Stun grenades170–180 dB Rocket launch equipment acoustic tests~165 dB Simple open-ended thermoacoustic device   176 dB rifle being fired 1 m to shooter's side171 dB (peak) M1 Garand rifle being fired at 1 m168 dB Jet engine at 30 m150 dB Threshold of pain130 dB Vuvuzela horn at 1 m120 dB(A)   Hearing damage (possible)approx. 120 dB Jet engine at 100 m110 – 140 dB Non-electric chainsaw at 1 m110 dB   Jack hammer at 1 mapprox. 100 dB Traffic on a busy roadway at 10 m80 – 90 dB Hearing damage (over long-term exposure, need not be continuous)85 dB   Passenger car at 10 m60 – 80 dB EPA-identified maximum to protect against hearing loss and other disruptive effects from noise, such as sleep disturbance, stress, learning detriment, etc. 70 dB   Handheld electric mixer65 dB TV (set at home level) at 1 mapprox. 60 dB Washing machine, dishwasher42-53 dB   Normal conversation at 1 m40 – 60 dB Very calm room20 – 30 dB Light leaf rustling, calm breathing10 dB Auditory threshold at 1 kHz0 dB   The Human Ear