Derivation of the speed sound

This video will present a derivation of the speed of sound.

[Snoopies]

Derivations of the speed of sound always feel like they have a hand-waving quality to me. I can follow the math, but something in the reasoning feels . . suspicious.

[dhruvvji]

Studying since 1 yr
Very good lecture

[FranzBond]

Because rho and Bulk Modulus are in function of the temperature.
The more temperature the medium has, the more dynamic forces is going to get, so the medium proprieties will change.
Mass behavior is in function of its internal and external energy.

[victormaxwellpeters]

How can you say V is the velocity of sound, where are the arguments that supports this context?? Why speed of sound needs to be constant in your explaination??? It should have depended on velocity of piston

[karanbhanushali]

Density changes thus Speed can change due to change in temperature

[Cnu_IIITian]

Two points assumed wrong in derivation

1. Bulk modulus of gas defines the ratio pressure applied to the strain. The pressure is not changing here, it's constant

So in the equation for derivation of impulse in your experiment of compression, the pressure is considered "on the volume under compression" which will not be constant & raise rapidly from P to P+ ∆P, this can be considered isentropic process as the process is quick or also can be considered isothermal if the temp change is not considerable.

But the ∆P is not constant through out the process for which the impulse is calculated.integral average with respect to time can be calculated to know it precisely.

2. In The m∆v evaluation, ∆v( velocity), the change in velocity of vx is considered which really affected the volume vx . A not vi.A. how can the affected m be rho x vi ?.

If the entire volume moved at Vx velocity, why will it be compressed.

[anandapatmanabhansu]

How does equation in 2:21 come teacher. Delta p value equation