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A) REsidents of the house use .35 m^3 of water per day. The day's pumping is completed in 2 hours during the day.

1) calculate the minimum work required to pump the water used per day

2) Calculate the minimum power rating of the pump

B) The average pressure the pump actually produces is 9.2X10^5 N/m^2. Within the well the water flows at .50 m/s and the pipe has a diameter of 3cm. At the house the pipe diameter is 1.25cm

1) Calculate the flow velocity when a faucet in the house is open

2) Explain how you could calculate the minimum pressure at the faucet

http://www.collegeboard.com/prod_downloads/ap/students/physics/b_physics_b_frq_03.pdf

picture here, problem #6

attemp solution

A)

1- M=DV

M=1000(.35)= 350kg = 350000g

W=mgh

W=350000(9.8)(30+50) 30from bottom to ground, 50 from ground to the house

W=274400000J

2- P=W/t

P= 274400000J/7200s 2hour=7200s

P=38111.1 Watt

B)

1- AV=AV

(.03/2)^2*pi*.05= (.0125/2)^2*pi*V

V=2.88 m/s

2- P=F/A

I know the area, but i dont know how to get the F,

I need a confirm, or any suggestion

Appreciate