Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

http://s10.postimg.org/bca4iyoah/12_3.gif An incompressible non-viscous fluid fl

ID: 2241971 • Letter: H

Question

http://s10.postimg.org/bca4iyoah/12_3.gif


An incompressible non-viscous fluid flows through a horizontal pipe that starts out with a certain radius (section A) and then widens to double the radius in section B. What happens to the flow velocity in section B, compared to section A?
Four times the velocity
Twice the velocity
Same velocity
Half the velocity
One fourth the velocity


How do the pressures in sections A and B compare?
Higher pressure in B than in A
Same pressure in both sections
Lower pressure in B than in A


Suddenly somebody closes a valve in section B, and the flow stops. How do the pressures in sections A and B compare now?
Higher pressure in B than in A
Same pressure in both sections
Lower pressure in B than in A

An incompressible non-viscous fluid flows through a horizontal pipe that starts out with a certain radius (section A) and then widens to double the radius in section B. What happens to the flow velocity in section B, compared to section A? Four times the velocity Twice the velocity Same velocity Half the velocity One fourth the velocity How do the pressures in sections A and B compare? Higher pressure in B than in A Same pressure in both sections Lower pressure in B than in A Suddenly somebody closes a valve in section B, and the flow stops. How do the pressures in sections A and B compare now? Higher pressure in B than in A Same pressure in both sections Lower pressure in B than in A

Explanation / Answer

Continuity Eqn => A1V1=A2V2

=>Since radius at section B = 2*radius at section A

=> Area B=4*Area A

=> V2=V1/4 => D option

Using Bernoullie's eqn=>P+1/2*Density*V^2 + Density*g*h=Constant

=> Since V2<V1=> Higher pressure in B =>Option A

Because of the closing of the valve back pressure at B will be generated which will transfer back to A=> Still Higher pressure in B => A