Most Important Selected Qs for JEE AdvancedPhysicsMechanical Properties of Fluids
Paragraph: A tube of length and radius R carries a steady flow of a fluid whose density is and viscosity . The velocity v of flow is given by v = v ₀ [1- ( r ^2 / R^2 ) ] , where r is the distance of flowing fluid from the axis. Then Question: The difference of pressure at the end of the tube is
Options
- A4 v₀ R^2
- B8 v₀ R^2
- C2 / v₀ R^2
- D/ v₀ R^2
Correct answer
A. 4 v₀ R^2
Step-by-step solution
aligned & P(2 r) d r=2 r d v d r -2 (r+d r) d v d r & P(2 r) d r=-2 ( d v d r ) d r & P(2 r)=-2 ( -2 v₀ r R^2 ) & P= 2 v₀ R^2 aligned