A. Passing the centroid of the body at 60°to the direction of motion
B. The component being parallel to the flow direction
C. The component being normal to the flow direction
D. None of these
Related Mcqs:
- Drag is defined as the force exerted by the___________________?
A. Fluid on the solid in a direction opposite to flow
B. Fluid on the solid in the direction of flow
C. Solid on the fluid
D. None of these - In which of the following body shapes, the pressure drag is large compared to the friction drag ?
A. Stream line body
B. Two dimensional body
C. Bluff body
D. None of these - The ratio of wall drag to total drag in the Stoke’s law range is_________________?
A. 0.5
B. 1
C. 1/3
D. 2/3 - The ratio of the wall drag to the form drag in the Stoke’s law range (for motion of spherical particles in a stationary fluid) is__________________?
A. 0.5
B. 1
C. 2
D. 0.33 - Drag co-efficient for flow past immersed body is the ratio of _____________ to the product of velocity head and density?
A. Shear stress
B. Shear force
C. Average drag per unit projected area
D. None of these - Deformation drag, which is caused by widespread deformation of fluid around the immersed body____________________?
A. Occurs when NRe is very small
B. Is primarily a friction drag
C. Is independent of body length
D. Depends mainly on cross-sectional shape - Which of the following relationship is valid for the equilibrium position of the float in a Rotameter? (Where, Df= Drag force on the float Bf = Buoyant force on the float Wf = Weight of the float)?
A. Df + Bf = Wf
B. Df = Bf + Wf
C. Df + Bf + Wf =0
D. None of these - The location of centre of pressure, which defines the point of application of the total pressure force on the surface, can be calculated by applying the principle of moments according to which “sum of the moment of the resultant force about an axis is equal to the sum of the components about the same axis”. The centre of pressure of a rectangular surface (of width ‘w’) immersed vertically in a static mass of fluid is at a depth of (where, y = depth of the liquid) ?
A. 1/(y/3)
B. 2y/3
C. 1/(y/4)
D. 3y/4 - Drag force on the float of a Rotameter is (where Q = flow rate of the)__________________?
A. ∝ Q
B. ∝ √Q
C. ∝ Q2
D. Constant - In the low Reynolds number region, the drag force on a sphere is proportional to_______________?
A. V
B. V2
C. V4
D. V0.5
