A. 20mm
B. 22.36mm
C. 25mm
D. 50mm
E. 100mm
Which is correct?
更新1:
Isn't that A1v1 = A2v2 (law of continunity) v2 = A1v1/A2 = (10^-4)v1/(100 x 10^-6) Why v2 = 10^-4 / 100 x 10^-6 ? Also, why v2² - v1² = v2² ?
Hydrodynamics
2009-07-23 6:05 am
Water flows into a tank of large cross-sectional area at a rate of 10^(-4) m^3/s, but flows out from a hole of area 100mm^2, which has been punched through the base. How high does the water rise in the tank?
A. 20mm
B. 22.36mm
C. 25mm
D. 50mm
E. 100mm
Which is correct?
A. 20mm
B. 22.36mm
C. 25mm
D. 50mm
E. 100mm
Which is correct?
回答 (1)
2009-07-23 1:41 pm
✔ 最佳答案
Let p be the density of water.Water velocity, v2 = 10-4 / 100 X 10-6 = 1 ms-1
By Bernoulli's principle,
P0 + 1/2 pv12 + pgh1 = P0 + 1/2 pv22 + pgh2
pg(h1 - h2) = 1/2 p(v22 - v12)
Rise in height, h1 - h2 = (1)2 / 2g
= 1 / 2(10)
= 0.05 m
= 50 mm
The answer is D.
參考: Physics king
收錄日期: 2021-04-19 15:01:36
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