Description : When the Mach number is less than unity, the flow is called (A) Sub-sonic flow (B) Sonic flow (C) Super-sonic flow (D) Hyper-sonic flow
Last Answer : Answer: Option A
Description : A flow is called sub-sonic, if the Mach number is (A) Less than unity (B) Unity (C) Between 1 and 6 (D) More than 6
Description : When the Mach number is more than 6, the flow is called (A) Sub-sonic flow (B) Sonic flow (C) Super-sonic flow (D) Hyper-sonic flow
Last Answer : Answer: Option D
Description : A flow is called super-sonic if the (A) Velocity of flow is very high (B) Discharge is difficult to measure (C) Mach number is between 1 and 6 (D) None of these
Last Answer : Answer: Option C
Description : When the Mach number is between __________ the flow is called super-sonic flow. (A) 1 and 2.5 (B) 2.5 and 4 (C) 4 and 6 (D) 1 and 6
Description : Mach number is defined as the ratio of the local flow velocity to the sonic velocity in the fluid. For what value of Mach number, the gases are considered incompressible? (A) < 0.3 (B) > 3 (C) 50 (D) 1
Last Answer : (A) < 0.3
Description : For hypersonic flow, the Mach number is (A) Unity (B) Greater than unity (C) Greater than 2 (D) Greater than 4
Description : Pick out the correct statement pertaining to the flow through a converging-diverging tube. (A) The value of Mach number is always unity at the throat (B) No shock wave develops in the tube ... the converging portion of the tube, the density increases in the downstream direction (D) None of these
Last Answer : (B) No shock wave develops in the tube when the Mach number at exit is greater than unity
Description : Pick out the correct statement. (A) Fanning friction factor is inversely proportional to Reynolds number always (B) The property of a randomly packed bed (with raschig rings) is given by the ratio of the ... the ratio of the speed of the fluid to that of sound in the fluid under conditions of flow
Last Answer : (D) Mach number is given by the ratio of the speed of the fluid to that of sound in the fluid under conditions of flow
Description : Which Country successfully launched a hyper-sonic Missile recently called as “an ideal weapon“? (a) Russia (b) USA (c) North Korea (d) None of These
Last Answer : (a) Russia
Description : The velocity at which the flow changes from laminar flow to turbulent flow is called (A) Critical velocity (B) Velocity of approach (C) Sub-sonic velocity (D) Super-sonic velocity
Description : Mach number is significant in (A) Supersonics, as with projectiles and jet propulsion (B) Full immersion or completely enclosed flow, as with pipes, aircraft wings, nozzles etc. (C) Simultaneous motion through ... gravity force, and wave making effects, as with ship's hulls (D) All of the above
Description : Pick out the wrong statement. (A) The shear stress at the pipe (dia = D, length = L) wall in case of laminar flow of Newtonian fluids is (D/4L). ∆p (B) In the equation, T. gc = k. ... to motion (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids
Last Answer : (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids
Description : The temperature in isentropic flow (A) Does not depend on Mach number (B) Depends on Mach number only (C) Cannot drop and then increase again downstream (D) None of these
Last Answer : (B) Depends on Mach number only
Description : Which of the following denotes the effect of compressibility in fluid flow? (A) Weber number (B) Mach number (C) Euler number (D) Reynolds number
Last Answer : (B) Mach numbe
Description : The Mach number for hypersonic flow of compressible fluid is (A) 1 (B) > 1 (C) > 4 (D) < 2
Last Answer : (C) > 4
Description : Mach number is important in a fluid flow problem, when the inertia and __________ forces predominate. (A) Elastic (B) Viscous (C) Gravity (D) None of these
Last Answer : (A) Elastic
Last Answer : A) Elastic
Description : In case of supersonic flow of a fluid through pipeline, the 'Mach number' is (A) 0 (B) 1 (C) < 1 (D) > 1
Last Answer : (D) > 1
Description : __________ number determines whether the fluid flow in an open channel is supercritical, critical or sub-critical. (A) Mach (B) Reynolds (C) Froude (D) Weber
Last Answer : (C) Froude
Description : The velocity corresponding to Reynold number of 2000 is called (A) Sub-sonic velocity (B) Super-sonic velocity (C) Lower critical velocity (D) Higher critical velocity
Description : The velocity corresponding to Reynold number of 2800, is called (A) Sub-sonic velocity (B) Super-sonic velocity (C) Lower critical velocity (D) Higher critical velocity
Description : Consider the following statements in respect of critical flow in a wide rectangular channel: 1. The specific energy is minimum for a given discharge. 2. The discharge is maximum for a given specific energy 3. The specific force is minimum for a ... b) 1, 2, 3 & 4 (c) 1, 2 & 4 only (d) 2, 3 & 4 only
Last Answer : (b) 1, 2, 3 & 4
Description : Surging basically implies A. Unsteady, periodic and reversed flow B. Forward motion of air at a speed above sonic velocity C. The surging action due to the blast of air produced in a compressor D. Forward movement of aircraft
Last Answer : ANSWER : A
Description : The ratio of the inertia force to the elastic force is called (A) Reynold's number (B) Froude's number (C) Weber's number (D) Mach number
Description : 08. The ratio of velocity of fluid in an undisturbed stream to the velocity of sound wave is known as Mach number. A) Yes B) No
Last Answer : A
Description : Ratio of inertia force to elastic force is known as (A) Mach number (B) Froude number (C) Reynolds number (D) Weber's number
Description : Ratio of inertia force to surface Jension is known as (A) Mach number (B) Froude number (C) (D) Weber's number
Description : The value of bulk modulus of a fluid is required to determine (A) Reynold's number (B) Froude's number (C) Mach number (D) Euler's number
Description : In actual machines (A) Mechanical advantage is greater than velocity ratio (B) Mechanical advantage is equal to velocity ratio (C) Mechanical advantage is less than velocity ratio (D) Mechanical advantage is unity
Last Answer : (C) Mechanical advantage is less than velocity ratio
Description : In ideal machines (A) Mechanical advantage is greater than velocity ratio (B) Mechanical advantage is equal to velocity ratio (C) Mechanical advantage is less than velocity ratio (D) Mechanical advantage is unity
Last Answer : (B) Mechanical advantage is equal to velocity ratio
Description : Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In ... layers over a flat plate are of equal thickness, if Schmidt number is equal to unity
Last Answer : (C) For Laminar flow over a plate of length L, the local mass transfer coefficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s
Description : Pick out the correct statement pertaining to Venturimeter. (A) A Venturimeter with a fixed pressure drop discharges more, when the flow is vertically downward, than when the flow is vertically upward (B ... , when compressibility is taken into account, than when it is neglected (D) None of these
Last Answer : (D) None of these
Description : The ratio of inertial forces to gravity forces is called the __________ number. (A) Mach (B) Froude (C) Euler (D) Weber
Last Answer : (B) Froude
Description : The ratio of inertial forces to elastic forces is called the __________ number. (A) Reynolds (B) Mach (C) Euler (D) Weber
Last Answer : (B) Mach
Description : Ratio of inertial forces to surface tension forces is called the __________ number. (A) Euler (B) Froude (C) Mach (D) Weber
Last Answer : (D) Weber
Description : The ratio of inertial forces to viscous forces is called the __________ number. (A) Weber (B) Mach (C) Froude (D) Reynold
Last Answer : (D) Reynold
Description : The ratio of pressure forces to inertial forces is called the __________ number. (A) Froude (B) Euler (C) Reynold (D) Mach
Last Answer : (B) Euler
Description : Mach number is used in connection with the speed of (a) Sound (b) Aircraft (c) Spacecraft (d) Ships
Last Answer : Ans:(b)
Description : Cp /Cv is termed as (A) Adiabatic constant (B) Mach number (C) Weber number (D) Prandtl number
Last Answer : (A) Adiabatic constan
Description : The co-efficient of drag and lift for an incompressible fluid depends on the (A) Reynolds number (B) Froude number (C) Mach number (D) All (A), (B) and (C)
Last Answer : (A) Reynolds numbe
Description : For ideally incompressible fluid, the Mach number will be (A) 1.5 (B) 1 (C) 0 (D) 5
Last Answer : (B) 1
Description : Ratio of pressure and inertia force gives __________ number. (A) Weber (B) Mach (C) Euler (D) Froude
Last Answer : (C) Euler
Description : Upto what value of 'Mach number', a fluid may be considered as incompressible? (A) 0.03 (B) 0.3 (C) 3 (D) 10
Last Answer : (D) 10
Description : Mach number is the ratio of the speed of the (A) Fluid to that of the light (B) Light to that of the fluid (C) Fluid to that of the sound (D) Sound to that of the fluid
Last Answer : (C) Fluid to that of the sound
Description : The molecular number density of an ideal gas at standard temperature and pressure in cm3 a. Froude number b. Loschmidt number c. Mach number d. Reynold number
Last Answer : Loschmidt number
Description : You are flying at a constant FL 290 and a constant mach number. The total temperature increases by 5°. The CAS will: a. Remain approximately constant b. Increase by 10 kts c. Decrease by 10 kts d. Will increase or decrease depending on whether you are above or below ISA
Last Answer : a. Remain approximately constant
Description : Comment on Mach number of steam in impulse and reaction turbines.
Last Answer : Mach number, in fluid mechanics, ratio of the velocity of a fluid to the velocity of sound in that fluid. Mach numbers less than one indicate subsonic flow; those greater than one, supersonic flow.