I know the answer, but I keep coming up with 8gh/3... Please help! If you need to see the illustration:
http://online.physics.uiuc.edu/cgi/courses/shell/phys101/spring11/prep2a.pl?practice/exam3/fa10
QUESTION 6***
An incompressible ideal liquid is flowing in the pipe illustrated below. The ratio of the cross sections of the ends is 2 (i.e. A2 / A1 = 2), and the height difference at the ends is h. The pressure is the same at the two ends (i.e. P2 = P1). Which one of the following is true?
(a) v2^2 = gh / 4
(b) v2^2 = gh / 2
(c) v2^2 = 2gh / 3
(d) v2^2 = gh
(e) v2^2 = 3gh / 2
http://online.physics.uiuc.edu/cgi/courses/shell/phys101/spring11/prep2a.pl?practice/exam3/fa10
QUESTION 6***
An incompressible ideal liquid is flowing in the pipe illustrated below. The ratio of the cross sections of the ends is 2 (i.e. A2 / A1 = 2), and the height difference at the ends is h. The pressure is the same at the two ends (i.e. P2 = P1). Which one of the following is true?
(a) v2^2 = gh / 4
(b) v2^2 = gh / 2
(c) v2^2 = 2gh / 3
(d) v2^2 = gh
(e) v2^2 = 3gh / 2
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(v1)/2 = (v2)²/2 + gh
A1 = (0.5)A2
v1 = 2v2
(2v2)²/2 = (v2)²/2 + gh
4(v2)²/2 = (v2)²/2 + gh
(4-1)(v2)²/2 = gh
3/2(v2)² = gh
(v2)² = 2gh/3 => ANS (c)
A1 = (0.5)A2
v1 = 2v2
(2v2)²/2 = (v2)²/2 + gh
4(v2)²/2 = (v2)²/2 + gh
(4-1)(v2)²/2 = gh
3/2(v2)² = gh
(v2)² = 2gh/3 => ANS (c)