Question

A water pipe 5cm in radius has a construction of radius 2cm.if the velocity of the flow of water in the main pile is 20cm/s.calculate the velocity of construction​

Answer 1

Answer:

Explanation:

(Poiseulli's theorem)

As the Q is constant along the pipe

⇒πPr/4​8ηL=8η(L−2)πP1​r4​

⇒LP​=L−2P1​​

⇒PL−2P=P1​L

⇒(P−P1​)L=2P

⇒P−P1​=L2P​-------------------(1)

Q=π10(10−2)2​=π×10−5m3/s  [from poiseulli's equation and equation]

⇒π×10−5=8×10−3×Lπ×P×(10−2)4​

⇒8×10−8=2×10−8×LP​⇒L2P​=8---------------(2)

From (1) and (2),

P−P1​=8