As the velocity V and thus the Reynolds number of a flow past a sphere increases from very low value, the drag force for Re << 1 (A) Increases linearly with V (B) Decreases linearly with V (C) Decreases as V2 (D) None of these

As the velocity V and thus the Reynolds number of a flow past a sphere
increases from very low value, the drag force for Re << 1
(A) Increases linearly with V
(B) Decreases linearly with V
(C) Decreases as V2
(D) None of these
by

1 Answer

Answer :

(A) Increases linearly with V
by

Related questions

. In case of turbulent flow of fluid through a circular pipe, the (A) Mean flow velocity is about 0.5 times the maximum velocity (B) Velocity profile becomes flatter and flatter with increasing Reynolds number (C) Point of maximum instability exists at a distance of 2r/3 from the pipe wall (r = pipe radius) (D) Skin friction drag, shear stresses, random orientation of fluid particles and slope of velocity profile at the wall are more

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Last Answer : (D) Skin friction drag, shear stresses, random orientation of fluid particles and slope of velocity profile at the wall are more

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Last Answer : (C) Average drag per unit projected area

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A spherical particle is falling slow in a viscous liquid such that Reynolds number is less than 1. Which statement is correct for this situation? (A) Inertial and drag forces are important (B) Drag, gravitational and buoyancy forces are important (C) Drag force and gravitational forces are important (D) None of the above

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