The condition for onset of turbulent flow is that the Reynolds Number reaches what value?
a. 1 000
b. 2 000
c. 3 000
d. 4 000
[Ques. 2] When an artery gets a constricted region due to plaque, how does the pressure in this region compare to the pressure in an unconstricted region adjacent?
a. Since this is a closed system, the pressure is the same in both regions.
b. In the constricted region the blood moves at a higher speed than in the unconstricted region resulting in an increased pressure.
c. In the constricted region the blood moves at a higher speed than in the unconstricted region resulting in a decreased pressure.
d. In the constricted region the blood moves at a lower speed than in the unconstricted region resulting in an increased pressure.
[Ques. 3] How much power is theoretically available from a mass flow of 1 000 kg/s of water that falls a vertical distance of 120 m?
a. 1.18E+6 kW
b. 1.20E+5 kW
c. 1.18E+3 W
d. 8.17E+1 W
e. 1.18E+6 W
[Ques. 4] Water is sent from a fire hose at 34.5 m/s at an angle of 30.0 above the horizontal. What is the maximum height reached by the water, assuming the fire hose is level with the ground?
a. 7.59 m
b. 15.2 m
c. 30.4 m
d. 300 m
e. 60.7 m
[Ques. 5] A jet of water flowing from a hose at 18 m/s is directed against a wall. If the mass flow in the fluid stream is 2.0 kg/s, what force is the water applying to the wall if backsplash is negligible?
a. 36 N
b. 0.11 N
c. 38 N
d. 350 N
e. 34 N
[Ques. 6] How much air must be pushed downward at 40.0 m/s to keep an 830-kg helicopter aloft?
a. 20.8 kg/s
b. 203 kg/s
c. 33 200 kg/s
d. 208 kg/s
e. 193 kg/s
[Ques. 7] Air pressure is 1.00 105 N/m2, air density is 1.30 kg/m3, and the density of soft drinks is 1.00 103 kg/m3 . If one blows carefully across the top of a straw sticking up 0.10 m from the liquid in a soft drink can, it is possible to make the soft drink rise half way up the straw and stay there. How fast must the air be blown across the top of the straw?
a. 0.036 m/s
b. 27 m/s
c. 1.4 m/s
d. 19 m/s
e. 750 m/s
[Ques. 8] The flow rate of blood through the average human aorta, of radius 0.95 cm, is about 90 cm3/s. What is the speed of the blood flow through the aorta?
a. 14 cm/s
b. 32 cm/s
c. 37 cm/s
d. 32 cm/s
[Ques. 9] A water pipe with inner radius r1 is connected to a junction with two equal-diameter pipes. Water flows through each of the two pipes with a speed of v. If the diameter of each of the two pipes is the diameter of the single pipe, what is the flow rate in the single pipe?
a. v/8
b. v/4
c. 4v
d. 8v
[Ques. 10] The fluid to which Bernoulli's equation is applied is based on what being conserved for the fluid?
a. its momentum b. its potential energy
c. its kinetic energy d. its total mechanical energy
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