Water is flowing in a horizontal pipe of variable cross section. Where the cross-sectional area is 1.0 x 10^(-2)m^2, the pressure is 5.0 x 10^5 Pa and the velocity 0.50 m/s. In a constricted region where the area is 4.0 x 10^-4 m^2, what are the pressure and velocity?
a. 12.5 m/s 4.2 x 10^5 Pa
b. 12 m/s 42 x 10^5 Pa
c. 12.5 m/s 42 x 10^5 Pa
d. 2.5 m/s 4.2 x 10^5 Pa
2006-08-07 03:28:48 · 2 answers · asked by Lou 1 in Science & Mathematics ➔ Physics
From continuity
Av = A'v'
so, v' = 50/4 m/s = 12.5m/s
P = 4.2 x 10^5 Pa
2006-08-07 04:02:01 · answer #1 · answered by ag_iitkgp 7 · 0⤊ 0⤋
The volume of water flowing through any cross section every second is the same. Therefore
4.0 x 10^ - 4 x velocity = 0.005
=> velocity = 12.5 ms^ -1
I can't figure out the part with the pressure. Sorry.
2006-08-07 04:27:36 · answer #2 · answered by jimmy_siddhartha 4 · 0⤊ 0⤋