The drag force is given by_________________?
Correct answer: D. Stokes law
- A. Newtons law
- B. Pascals law
- C. Gauss law
- D. Stokes law
Explanation
For a small sphere moving slowly through a viscous fluid, Stokes' law gives drag force F = 6π η r v, where F is in N, η in Pa·s, r in m and v in m/s. Students may choose Newton's law because it describes motion generally, but Stokes' law specifically gives viscous drag in this situation.
Last updated
About Fluid Drag
Fluid drag is the resistive force exerted by a liquid or gas on an object moving through it, and its value depends on speed, fluid density, shape and exposed area. Questions examine drag at low and high speeds, terminal velocity when drag balances weight, and the difference between drag and ordinary solid friction.
Practise Fluid Dynamics
363 free Fluid Dynamics MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 13 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
A bullet train is lifted above the rails due to magnetic effect, thus friction is reduced to minimum and speed can be enhanced up to:
According to Stokes's law, the drag force on a small sphere moving slowly through a viscous fluid is proportional to
As the temperature rises, the viscosity of a liquid
In cricket when a bowler produce reverse swing the ball will move towards______________?
In Milikan's Method, the radius of droplet can be calculated by: