physics
2010-01-09 7:05 am
Water circulates throughout a house in a hot-water heating system. If water is pumped out at a speed of 0.50 m/s through a 4.0 cm diameter pipe in the basement under a pressure of 3.0 atm, what will be the flow speed and pressure in a 2.6 cm diameter pipe on the second floor 5.0 m above? Assume pipes do not divide into branches.
回答 (2)
2010-01-10 7:13 am
無最佳解答
2010-01-09 8:55 am
Use Bernouli's Principle
(1/2)(1000)(0.5)^2 + 3x10^5 = (1/2)(1000)v^2 + p + (1000)g(5) ------ (1)
where 1000 kg/m3 is the density of water, and g is the acceleration due to gravity
From the continuity equation:
pi(4/2)^2 x 0.5 = pi(2.6/2)^2 x (v)
where pi = 3.14159.....
hence, v = (4/2.6)^2 x 0.5 m/s
substitute the value of v into (1) to find p(in unit of N/m2)
(1/2)(1000)(0.5)^2 + 3x10^5 = (1/2)(1000)v^2 + p + (1000)g(5) ------ (1)
where 1000 kg/m3 is the density of water, and g is the acceleration due to gravity
From the continuity equation:
pi(4/2)^2 x 0.5 = pi(2.6/2)^2 x (v)
where pi = 3.14159.....
hence, v = (4/2.6)^2 x 0.5 m/s
substitute the value of v into (1) to find p(in unit of N/m2)
收錄日期: 2021-04-29 17:31:35
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100108000051KK01724