It can be defined as the square root of the ratio of the inertia force of flowing liquid to the elastic force.

Mach Number=M

$\therefore M=\sqrt{\dfrac{\text{Inertia Force}}{\text{Elastic Force}}}$

$M=\sqrt{\dfrac{\rho AV^2}{KA}}$

$M=\sqrt{\dfrac{V^2}{\dfrac K\rho}}$

$M=\dfrac{V}{\sqrt{\dfrac K\rho}}$

Hence, $\left[M=\dfrac Vc\right]$

Significance of Mach number:-

The flow is defined according to the mach number, …