Shear strees

[Maqboole]

hi i m trying do this question but i just dont understand how .i would be thankful if someone guides me .

1 :-

The wall shear strees ina fully developed flow portion 0.3m diameter pipe carying water is 89 pa. dertermine the preasure gradient(Pa/m) if the pipe is

 

a :- Horizontal

b :- Vertical with flow up or

c :- Vertical With flow down.

 

2:-

A viscous fluids flows in a 0.10m diameter pipe, such that its velocity is measured 0.012m away from the pipe wall si 0.8 m/s. if the flow is lamiaar.

 

Dertermine the center veocity

Dertermine the flowrate/.

 

 

Thanks .