FLUID MECHANICS MCQ SET 3
Q1. Turbulent flow occurs when Reynolds number is:
A) < 2000
B) > 4000
C) Between 1000โ2000
D) Zero
Answer: B) > 4000
Explanation: For high Reynolds numbers, inertial forces dominate, causing turbulence.
Q2. The instrument used to measure discharge in an open channel is:
A) Orifice meter
B) Notch
C) Pitot tube
D) Piezometer
Answer: B) Notch
Explanation: Notches like V-notch or rectangular notch are used to measure open channel discharge.
Q3. Which equation represents the conservation of energy for fluid flow?
A) Pascalโs Law
B) Bernoulliโs Equation
C) Continuity Equation
D) Newtonโs Law
Answer: B) Bernoulliโs Equation
Explanation: Bernoulliโs equation relates pressure, kinetic, and potential energy along a streamline.
Q4. The velocity of fluid is maximum:
A) At the pipe wall
B) At the center of the pipe
C) At mid-radius
D) Uniform throughout
Answer: B) At the center of the pipe
Explanation: Due to friction at the walls, velocity is highest at the pipe center in laminar flow.
Q5. The ratio of shear stress to rate of shear strain is called:
A) Density
B) Viscosity
C) Velocity
D) Pressure
Answer: B) Viscosity
Explanation: Viscosity defines the internal resistance of fluid to flow, proportional to shear stress and strain rate.
Q6. The pressure intensity at a point in a fluid at rest depends on:
A) Depth below the surface
B) Density of the fluid
C) Acceleration due to gravity
D) All of the above
Answer: D) All of the above
Explanation: Pressure in a static fluid = ฯgh, hence depends on density (ฯ), depth (h), and gravity (g).
Q7. The center of pressure is defined as:
A) Point where total pressure acts
B) Center of gravity of the body
C) Midpoint of the surface
D) Point of minimum pressure
Answer: A) Point where total pressure acts
Explanation: Center of pressure is the point of application of the resultant hydrostatic force on a submerged surface.
Q8. Pascalโs law states that:
A) Pressure at a point is equal in all directions
B) Pressure depends on volume
C) Pressure decreases with area
D) None of the above
Answer: A) Pressure at a point is equal in all directions
Explanation: Pascalโs law states that any pressure applied to a confined fluid is transmitted equally in all directions.
Q9. A floating body displaces a volume of fluid equal to:
A) Its own weight
B) Its own volume
C) The fluidโs volume
D) None
Answer: A) Its own weight
Explanation: According to Archimedesโ principle, a floating body displaces fluid equal to its own weight.
Q10. A submerged body experiences:
A) Weight only
B) Buoyant force
C) Both weight and buoyant force
D) Zero force
Answer: C) Both weight and buoyant force
Explanation: Submerged bodies are acted upon by downward weight and upward buoyant force.
Leave a Reply