1. An incompressible fluid flows steadily upward through a circular pipe, as shown in the diagram in cross section. The diameter of the wide section is greater than that of the narrow section by a factor of 2.3. The ratio of flow speeds vn/vw is most nearly
5.3
2.3
1.0
0.43
0.19
2. A stream of water is flowing through a horizontal configuration. The speeds v 1 and v 2 are 3.25 m/s and 5.35 m/s, respectively. The pressure P2 is 7.36×104 Pa. What is P1? (The water is flowing to the right)
3. A shipwrecked mariner is stranded on a desert island. He seals a plea for rescue in a 1.00 liter bottle, corks it up, and throws it into the sea. If the mass of the bottle, plus the message and the air inside, is 0.450 kg, what percentage of the volume of the bottle is submerged as it bobs away? Take the density of seawater to be 1030 kg/m3. For simplicity, assume the bottle and its contents have a uniform density.
(For this one, I got 0.04% but this was wrong.)
5.3
2.3
1.0
0.43
0.19
2. A stream of water is flowing through a horizontal configuration. The speeds v 1 and v 2 are 3.25 m/s and 5.35 m/s, respectively. The pressure P2 is 7.36×104 Pa. What is P1? (The water is flowing to the right)
3. A shipwrecked mariner is stranded on a desert island. He seals a plea for rescue in a 1.00 liter bottle, corks it up, and throws it into the sea. If the mass of the bottle, plus the message and the air inside, is 0.450 kg, what percentage of the volume of the bottle is submerged as it bobs away? Take the density of seawater to be 1030 kg/m3. For simplicity, assume the bottle and its contents have a uniform density.
(For this one, I got 0.04% but this was wrong.)
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1.v varies as 1/d^2
So, (2.3)^2 = 5.3
2. = 7.36E4 + 0.5 x 10^3 x (5.35^2 - 3.25^2) = 8.26E4 Pa
3.Volume submerged = 0.450/1030 = 4.3689 x 10^-4 m^3 = 0.43689 liter
So, percentage of the volume of the bottle submerged = 43.69%
So, (2.3)^2 = 5.3
2. = 7.36E4 + 0.5 x 10^3 x (5.35^2 - 3.25^2) = 8.26E4 Pa
3.Volume submerged = 0.450/1030 = 4.3689 x 10^-4 m^3 = 0.43689 liter
So, percentage of the volume of the bottle submerged = 43.69%