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

Water at a gauge pressure of P = 5.8 atm at street level flows into an office bu

ID: 1286806 • Letter: W

Question

Water at a gauge pressure of P = 5.8 atm at street level flows into an office building at a speed of 0.90m/s through a pipe 5.6 cm in diameter. The pipe tapers down to 3.0 cm in diameter by the top floor, 16 m above (Figure 1) , where the faucet has been left open. Assume no branch pipes and ignore viscosity.

Part A

Calculate the flow velocity.

Express your answer to two significant figures and include the appropriate units.

Part B

Calculate the gauge pressure in the pipe on the top floor.

Water at a gauge pressure of P = 5.8 atm at street level flows into an office building at a speed of 0.90m/s through a pipe 5.6 cm in diameter. The pipe tapers down to 3.0 cm in diameter by the top floor, 16 m above (Figure 1) , where the faucet has been left open. Assume no branch pipes and ignore viscosity. no title provided Part A Calculate the flow velocity. Express your answer to two significant figures and include the appropriate units. Part B Calculate the gauge pressure in the pipe on the top floor.

Explanation / Answer

a)

From equation of continuity

A1V1=A2V2

=>V2=(A1/A2)V1

since A=pi*d2/4

V2=(d1/d2)2V1=(5.6/3)2*0.9

V2=3.136 m/s=3.1 m/s (upto 2 significant figures)

b)

From bernoulli's theorem

P1+(1/2)pV12+pgh1=P2+(1/2)pV22+pgh2

P1+(1/2)*1000*0.92+1000*9.8*0=P2+(1/2)*1000*3.12+1000*9.8*16

P1-P2=1.612*105 pascals

1 atm=9.86923267*10-6 atm

P1-P2=1.612*105*(9.86923267*10-6)=1.6 atm

P2=P1-1.6 =5.8-1.6

P2=4.2 atm