Fluid Mechanics - Study Mode
[#256] What is the ratio of the velocity at the axis of the pipe to the mean velocity of flow in case of pipe flow under viscous condition?
Correct Answer
(D) 2
[#257] Deformation drag, which is caused by widespread deformation of fluid around the immersed body
Correct Answer
(A) Occurs when N Re is very small
[#258] For an ideal fluid flow, Reynolds number is
Correct Answer
(D) ∞
[#259] For ideally incompressible fluid, the Mach number will be
Correct Answer
(C) 0
Explanation
Solution: The Mach number ($${Ma}$$) is a dimensionless quantity representing the ratio of the speed of an object (or fluid) to the speed of sound in the medium through which it is traveling. It is defined as: $${Ma} = frac{v}{c}$$ where: $${v}$$ is the velocity of the object or fluid. $${c}$$ is the speed of sound in the medium. For ideally incompressible fluids, the speed of sound is infinite, and thus the Mach number ($${Ma}$$) is zero. This is because in an incompressible fluid, changes in pressure do not affect the density of the fluid. Therefore, the speed of sound in such a fluid is infinitely high, and any velocity of the fluid will result in a Mach number of zero. Therefore, the correct answer is Option C: 0 .
[#260] Ratio of pressure and inertia force gives __________ number.
Correct Answer
(C) Euler