The square root of the ratio of the inertia force due to flow to the elastic force of fluid is known as-

Explanation

Explanation: Mach number Mach number is defined as the ratio of inertia force to elastic force. For the compressible fluid flow, Mach number is an important dimensionless parameter. On the basis of the Mach number, the flow is defined. M = ​ = ​ Elastic force Inertia force ​ = ​ KA ρAV 2 ​ = ​ ​ ρ K V 2 ​ = ​ ​ ρ K V ​ ​ = C = V elocity of sound C V { ​ ρ K } M = ​ velocity of sound in fluid V elocity of body moving in fluid Mach Number Type of flow M 5 Hypersonic flow Important Points Other important dimensionless numbers are described in the table below Reynold’s number Froude Number Euler number Weber Number R = e ​ = viscousforce inertiaforce ​ μ ρVL F ​ = r ​ = ​ gravitation force inertia force ​ ​ Lg V E ​ = u ​ = ​ pressure force inertia force ​ ​ P/ρ V W ​ = e ​ = ​ surface tension inertia force ​ ​ σ/ρL V