Travelling Sound

Question 1

Define inverse square law

Answer 1

The intensity at any given distance is proportional to intensity at original source divided by distance squared. Basically every time you double the distance the intensity drops by 6dB

Question 2

Define reflection

Answer 2

If a sound is not absorbed or transmitted when it hits a surface it is reflected. Sound waves travelling towards surface are direct sound waves and sound waves reflected back are indirect sound waves.

Question 3

Define echo

Answer 3

It is the delayed return of sound perceived as a repetition of the original sound produced by reflection with an audible gap.

Question 4

Define reverberation

Answer 4

When reflection occurs but causing a persistent sound due to multiple simultaneously occurring reflective sound waves. Time it takes for intensity of sound to decrease by 60dB is reverberation time

Question 5

Define resonance

Answer 5

The continuation of sound due to reflection. It vibrates with increasing amplitude at some frequencies of excitation

Question 6

Define diffusion

Answer 6

The scattering of sound. High frequencies diffuse better than they reflect.

Question 7

In phase vs out of phase

Answer 7

When two waves overlap with eachother if they are both in phase (I sync with eachother) then it is constructive interference as it enhances amplitude.
If they are out of phase (not in sync) then it is destructive interference and they cancel eachother aid, resulting in little to no sound.

Question 8

define warble tone

Answer 8

A frequency modulated tone used as an alternative for pure tone. Useful for kids and tinnitus sufferers.

Question 9

Define the Doppler effect

Answer 9

The relationship between perception of a waveform and the speed of the sound source.