Question

How to convert Sound waves into heat.

Answer 1

.... yell at a boyscout?

Answer 2

Thermodynamic and fluid-dynamic processes in sound waves in gases can convert energy from one form to another.In these thermoacoustic processes ,acoustic power can produce heat.

Answer 3

take "the clapper" and make it short circuit ....

Answer 4

you can see that from c=P'/p this is the state equation of sound waves (longitudinal waves)

Answer 5

sorry c^2=P'/p Historically,Newton found that equation experimentally,measured in gases that follow adiabatic isentropic procedures

Answer 6

for an ideal gas PV=nRT that means with the increase of pressure the temperature is increased somewhat, you can see that way too

Answer 7

C^2=P'/p ---->c^2=γRT0/M you can see the dependence of the speed of sound with temperature and you can see it from the speed of propagation in air that is dependent of the temperature as well

Answer 8

This theory actually implemented by NASA. When space shuttle is launched due to release of huge amount of energy Deadly sound waves are produced that restrikes the shuttle and disturbs its lift. To avoid this Sound waves are converted into other form of energy.

Answer 9

that means that the pressure will be analogous to temperature as well, so every time you change the pressure in relation to p reference the temperature of an ideal gas( that is air and many of gases that the sound is propagated) is increased somewhat

Answer 10

I am in a confusion that, to what form are these sound waves converted.

Answer 11

in your example heat produces acoustic waves

Answer 12

what are acoustic waves.

Answer 13

longitudinal waves (like when you have a piston and you press it inside a duct with fluid in it), they produce areas with compression and expansion (x-axis) in comparison to transverse waves that are on the y-axis (like for example a string) ,when you produce sound you create areas of compression and expansion in air ,that is the medium (like the fluid in the duct i mentioned before)

Answer 14

imagine the molecules of air when you shout moving back and forth (compressed and expanded all the time)

Answer 15

Fine.
Just now my said that water bubbles are good absorbers of sound waves. why and how.

Answer 16

when sound waves strike water bubbles they absorb them and then waves converted into heat with in. How this works.

Answer 17

bubbles are pretty difficult to understand in terms of physics...they have non-linear response to the sound waves
basically the bubbles work as scatterers--->they attenuate the sound wave ,it is like absorption
For an incident plane sound wave of intensity I0 the power removed by each bubble is σΙ0 and the rate of change of idensity as a beam travels through N bubbles is given by
dI/dx=-I0σN ---->I=I0exp(-σNx) (where σ is the extinction cross sextion of the bubble)

So you see that the bubbly medium changes the sound speed,absorbs sound and it is dispersive.

Answer 18

you see from the exponential function i mean that the intensity decreases as the sound moves through the bubble

Answer 19

i explained above why the sound decreases in the bubble but lets see why the temperature is increased

Answer 20

bubbles like all fluids have some thermal conductivity and viscosity and the bubble changes the compressibility of the medium veeery much (i wont go into details there are many complicated equations about that) .So when you change the compressibility so the pressure of a fluid that has an analogous performance as that of the ideal gas you increase the temperature (as i said PV=nRT)

Answer 21

its great.
thank you so much.

Answer 22

you 're welcome