SSC JE Exam - fluid kinematics streamlines laminar turbulent flow continuity equation Online Test (MCQ Quiz)

1. What does fluid kinematics primarily study?

A) The forces acting on a fluid B) The motion of fluids without considering the forces causing motion C) The energy transfer within a fluid D) The properties of fluid at rest

2. Which of the following is a path traced by a single fluid particle over time?

A) Streamline B) Pathline C) Streakline D) Streamtube

3. A streamline is defined as a line drawn in a fluid such that:

A) It is always parallel to the velocity vector of the fluid particle passing through it B) It is always perpendicular to the velocity vector of the fluid particle passing through it C) It represents the path of a stationary fluid particle D) It shows the concentration of fluid particles at a given instant

4. In steady flow, which of the following is true?

A) Streamlines, pathlines, and streaklines are identical B) Streamlines and pathlines are identical, but streaklines may differ C) Pathlines and streaklines are identical, but streamlines may differ D) Streamlines, pathlines, and streaklines are always different

5. What is a streamtube (or stream filament)?

A) A single streamline B) A bundle of adjacent streamlines C) A line representing the instantaneous velocity D) A line representing the trajectory of a particle

6. In a streamtube, the flow is such that:

A) Fluid can cross the boundary of the streamtube B) No fluid can cross the boundary of the streamtube C) The velocity is constant across the boundary D) The pressure is constant across the boundary

7. Laminar flow is characterized by:

A) Random and chaotic fluid motion B) Smooth, orderly fluid motion in layers C) High velocity and mixing of fluid D) Formation of eddies and vortices

8. Turbulent flow is characterized by:

A) Smooth, layered motion B) Predictable particle paths C) Irregular, chaotic motion with eddies and mixing D) Very low velocities

9. Which type of flow is typically observed at very low velocities or in highly viscous fluids?

A) Turbulent flow B) Laminar flow C) Transitional flow D) Superfluid flow

10. Which type of flow is typically observed at high velocities or in low viscosity fluids?

A) Laminar flow B) Transitional flow C) Turbulent flow D) Potential flow

11. The Reynolds number is a dimensionless quantity used to predict the transition between which two types of flow?

A) Steady and unsteady flow B) Compressible and incompressible flow C) Laminar and turbulent flow D) Ideal and real flow

12. A low Reynolds number generally indicates:

A) Turbulent flow B) Laminar flow C) Transitional flow D) Separated flow

13. A high Reynolds number generally indicates:

A) Laminar flow B) Turbulent flow C) Potential flow D) Steady flow

14. The continuity equation is a statement of the principle of:

A) Momentum conservation B) Energy conservation C) Mass conservation D) Angular momentum conservation

15. For one-dimensional, steady flow of an incompressible fluid, the continuity equation can be expressed as:

A) A1*V1 = A2*V2 B) A1/V1 = A2/V2 C) A1+V1 = A2+V2 D) A1*V1*rho1 = A2*V2*rho2

16. In the continuity equation A1*V1 = A2*V2 for incompressible flow, A represents:

A) Area of the flow cross-section B) Velocity of the fluid C) Density of the fluid D) Length of the flow path

17. If the cross-sectional area of a pipe carrying an incompressible fluid decreases, what happens to the velocity of the fluid, assuming steady flow?

A) It decreases B) It increases C) It remains constant D) It becomes zero

18. The continuity equation in its differential form for a steady, incompressible flow is:

A) ∂u/∂x + ∂v/∂y + ∂w/∂z = 0 B) ∂u/∂x + ∂v/∂y + ∂w/∂z = 1 C) ∂u/∂x + ∂v/∂y + ∂w/∂z = ρ D) ∂u/∂x + ∂v/∂y + ∂w/∂z = constant

19. In the differential form of the continuity equation (∂u/∂x + ∂v/∂y + ∂w/∂z = 0), u, v, and w represent:

A) Pressure components B) Velocity components in x, y, and z directions C) Density components D) Temperature components

20. For a 2D, steady, incompressible flow, the continuity equation simplifies to:

A) ∂u/∂x + ∂v/∂y = 0 B) ∂u/∂x - ∂v/∂y = 0 C) ∂u/∂y + ∂v/∂x = 0 D) ∂u/∂y - ∂v/∂x = 0

21. What is a potential flow?

A) Flow dominated by viscous forces B) Flow that is rotational C) Flow that is irrotational and inviscid D) Flow with significant turbulence

22. In fluid kinematics, a rotational flow is one where:

A) Fluid particles move in straight lines B) Fluid elements do not rotate about their own axes C) Fluid elements rotate about their own axes D) The flow is irrotational

23. An irrotational flow is one where:

A) Fluid elements rotate significantly B) The vorticity is non-zero C) The vorticity is zero D) The flow is highly turbulent

24. The velocity potential function, Φ, exists for which type of flow?

A) Rotational flow only B) Irrotational flow only C) Both rotational and irrotational flow D) Turbulent flow only

25. The condition for the existence of a velocity potential function for an incompressible flow is:

A) ∇ × V = 0 (irrotational) B) ∇ ⋅ V = 0 (incompressible) C) ∇ × V ≠ 0 D) ∇ ⋅ V ≠ 0

26. The stream function, ψ, is defined for which type of flow in two dimensions?

A) Compressible and rotational B) Incompressible and rotational C) Incompressible and irrotational D) Incompressible flow (rotational or irrotational)

27. For a 2D incompressible flow, the relationship between the stream function (ψ) and velocity components (u, v) is given by:

A) u = ∂ψ/∂y, v = -∂ψ/∂x B) u = -∂ψ/∂y, v = ∂ψ/∂x C) u = ∂ψ/∂x, v = ∂ψ/∂y D) u = -∂ψ/∂x, v = -∂ψ/∂y

28. What is the physical significance of the difference in stream function values between two streamlines?

A) It represents the velocity difference B) It represents the pressure difference C) It represents half the mass flow rate per unit width between the streamlines D) It represents the volume flow rate per unit width between the streamlines

29. In a steady flow, the difference in the stream function between two adjacent streamlines represents:

A) The pressure gradient B) The velocity component normal to the streamlines C) The volume flow rate per unit depth between the streamlines D) The dynamic viscosity

30. Which equation relates velocity components and their derivatives for a steady, incompressible flow?

A) Bernoulli's Equation B) Navier-Stokes Equation C) Continuity Equation D) Euler's Equation

31. Consider flow through a converging nozzle. If the fluid is incompressible and the flow is steady, what happens to the flow velocity as the area decreases?

A) Decreases B) Increases C) Remains constant D) Becomes zero

32. The concept of streamlines is most useful for visualizing:

A) The temperature distribution in a fluid B) The pressure variation in a fluid C) The direction of fluid velocity at any point D) The density changes in a fluid

33. Which of the following is a characteristic of turbulent flow that is generally absent in laminar flow?

A) Smooth, layered motion B) Predictable particle trajectories C) Eddy formation and significant mixing D) Viscous dissipation as the primary energy loss mechanism

34. The critical Reynolds number for flow in a pipe is approximately:

A) 100 B) 500 C) 2300 D) 10000

35. Flow in a very wide and shallow channel with a low velocity is likely to be:

A) Turbulent B) Transitional C) Laminar D) Chaotic

36. The continuity equation in integral form for steady flow states that the net rate of mass flow across a control surface is:

A) Zero B) Equal to the mass within the control volume C) Equal to the rate of change of mass within the control volume D) Equal to the sum of velocities

37. If the flow is unsteady, the continuity equation in differential form becomes:

A) ∂u/∂x + ∂v/∂y + ∂w/∂z = 0 B) ∂u/∂x + ∂v/∂y + ∂w/∂z = ∂ρ/∂t C) ∂u/∂x + ∂v/∂y + ∂w/∂z = -∂ρ/∂t D) ∂u/∂x + ∂v/∂y + ∂w/∂z = ρ

38. Which of the following is a consequence of the continuity equation for incompressible flow?

A) Velocity must be constant everywhere B) Area cannot change along the flow path C) If area decreases, velocity must increase D) If area increases, velocity must increase

39. The term 'kinematics' in fluid kinematics refers to the study of:

A) Forces and pressures B) Motion and its description C) Energy and work D) Thermodynamic properties

40. Which type of line shows the instantaneous positions of all fluid particles that have passed through a given point over a period of time?

A) Streamline B) Pathline C) Streakline D) Timeline

41. For a fluid flow to be classified as 'steady', the velocity at any given point must:

A) Be zero B) Be constant over time C) Vary with time D) Be zero in the direction of flow

42. Which flow regime is characterized by the absence of significant viscous effects and fluid compressibility?

A) Laminar flow B) Turbulent flow C) Potential flow D) Viscous flow

43. In turbulent flow, the velocity at any point fluctuates:

A) Smoothly and predictably B) Randomly and chaotically C) Linearly with time D) With zero frequency

44. The ratio of inertial forces to viscous forces in a fluid flow is represented by which dimensionless number?

A) Froude Number B) Weber Number C) Mach Number D) Reynolds Number

45. The continuity equation in its general form for a control volume is based on the principle that:

A) Energy is conserved B) Momentum is conserved C) Mass is conserved D) Angular momentum is conserved

46. For a 2D incompressible flow, if u = 2x and v = -2y, what is the continuity equation's implication?

A) The flow is rotational B) The flow is irrotational C) The flow satisfies continuity (∂u/∂x + ∂v/∂y = 0) D) The flow does not satisfy continuity

47. Which of the following is NOT a primary characteristic used to describe fluid motion in kinematics?

A) Velocity B) Acceleration C) Pressure D) Vorticity

48. The condition ∂u/∂x + ∂v/∂y + ∂w/∂z = 0 is the mathematical representation of the continuity equation for:

A) Compressible flow B) Steady flow C) Incompressible flow D) Unsteady flow

49. In the context of fluid kinematics, a 'streakline' is:

A) The path of a single fluid particle B) A line drawn tangent to the velocity vector C) The locus of points of all particles that have passed through a fixed point D) A bundle of adjacent streamlines

fluid kinematics streamlines laminar turbulent flow continuity equation - Online Test

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