![sound waves reflection refraction diffraction sound waves reflection refraction diffraction](https://i.pinimg.com/originals/1e/f0/80/1ef08049c2cc742fa1da608a735928d9.jpg)
Frequency will be decreased when the source increases the distance from the sensor (listener).
![sound waves reflection refraction diffraction sound waves reflection refraction diffraction](https://www.teachmeaudio.com/application/files/8815/8670/0688/refraction.png)
Frequency will be increased when the source approaches the sensor (listener),.The frequency of the wave is changed by the motion of the source,.DESTRUCTIVE INTERFERENCE -The displacement of the disturbance of TWO waves are the different (Unlike sounds) -Frequency are the different or not a direct multiple.-The displacement of the disturbance of TWO waves are the same (Similar sounds).The result of two or more sound or waves overlapping.So the resonance is frequency of sound waves exactly matches the natural frequency of an object.This is because the second tuning fork has started vibrating sympathetically.Strike one tuning fork so that you can hear its tone, and then suddenly silence it.Put two tuning forks of equal frequencies side by side, but not touching.If someone pushes you at random intervals, the chances will not cause you to swing very much higher, but if the pushing is in tune with your natural frequency, you can go very high indeed.The pushing has to be at the correct frequency, however. If someone pushes you at the right time, the amplitude of your swing increases. This buildup is known as resonance or sympathetic vibration.A driving force in tune with the natural frequency (sometimes known as the resonant frequency) of an oscillator can buildup larger amplitudes than the oscillator could alone.Speed of Sound MediumVelocity m/sec Air (20 C) 343 Air (0 C) 331 Water (25 C) 1493 Sea water 1533 Diamond12000 Iron 5130 Copper 3560 Glass 5640 On a cold night, the speed of sound is slower near the ground than above, so we can hear over larger distances.Sound waves tend to bend away from warm ground, since it travels faster in warmer air.This happens in uneven winds or temperatures.Sound waves are refracted when parts of a wave front travel at different speeds.The walls of concert halls are designed to make the reflection of sound diffuse.Reverberations- Multiple reflections of sound within a room.If the marchers in a given line all move from the pavement to the sand at. The marchers move faster on the pavement than in the sand. You can see how this happens by looking at lines of marchers with their arms intertwined moving from pavement onto sand. Acoustics is the study of the way sound reflects off of objects in a room This occurs because light moves more slowly in water than in air.Sound reflects from all surfaces of a room.Treble : High frequency, Above “middle range” note, 6,000 to 20,000 Hz.Standard Temperature and Pressure = 3.31 x 102 m/s.A medium is a material through which sound, a form of energy, need to transfer.Sounds can be changed by the Acoustics of the Area or the speed of the source (Doppler Effect),.Sounds are measured by Frequency, Wavelength, Speed, and Amplitude,.Sounds are created by Moving molecule in the medium ( Solid, Liquid and Gases),.SOUND WAVES, REFLECTION & REFRACTION Lecture No.