Honors Solids / Fluids Review Worksheet
1. Calculate the pressure created by ocean water (density = 1.025 g/cm3), at a depth of 11.0 Km.
2. The pressure in a tightly closed building is the same as outside, 1.01 x 105 Pa. The windows in this building are 1.2 m by 2.15 m. If a 23 m/s gust suddenly blows across the face of this building
a. What pressure difference across these windows does the wind create?
b. What force acts on each window?
3. A tennis ball has a density of 0.084 g/cm3 and a diameter of 3.8 cm. What force is required to submerge the ball in water?
4. Air pressure is 1x105 N/m2, air density is 1.3 kg/m3. How fast must air be blown across the top of a straw rising 0.10 m above the water in a glass, to make the water rise half way up the straw?
5. At what depth will a submersible experience 10.0 N per square millimeter pressure?
6. What lift does Bernoulli's principle predict for a wing of area 78 m2 if the air passes over the top surface at 260 m/s and the bottom surface at 150 m/s?
7. In liquid A, a body floats with 9/10th of its volume immersed, while in liquid B it floats with 3/5th of its volume immersed. Compare the densities of the liquids.
8. The average velocity of flow in a river is 1.1 m/s where it is 0.5 m deep and 5 m wide. (A) What is its flow rate? (B) Another part of the river it is 2 m wide and 1 m deep. What are the flow rate and the average velocity?
9. A thin hollow sphere of mass 0.500 kg and diameter 0.180 m is filled with alcohol (ρ= 806 kg/m3). Find the acceleration of the sphere after it is released under water.
10. A helium balloon tied by light string to an armrest in a stationary train hovers in the still air. When the train accelerates forward, what does the balloon do?
11. Lauryn has sculpted an irregular shaped copper object that she would really like to find the volume of. If she suspends it from a spring scale it reads 10 N. When she suspends the mass in a container of seawater the spring scale reads 9.2 N. What must the volume of Lauryn’s copper art be?
12. An iron anchor has a volume of 375 cm3 at sea level. It is lowered to a depth of 1 km under the ocean where the pressure exceeds atmospheric pressure by 100 atm. How much does the anchor’s volume decrease when it is lowered?
13. A cube of pine wood 50mm on an edge is held in the jaws of a vise by a force of 2000N. By how much is the wood compressed? Ypine = 1 x 1010 Pa
14. Eddie is driving his car and gets a flat tire. He pulls out his hydraulic jack to lift his car. If he exerts a force of 83 N on the handle of the jack and the diameter of the input piston is 125 mm, then what must the diameter of the output piston be if his car is 1100 kg?
15. Mr. Bruening bought his wife a “gold” bracelet from a guy on the street for $50. If he drops it in a beaker of water and the volume raises 3002 cm3 and the mass is determined to be 29.67 kg, then is the jewelry gold? If it is not gold then what do you think it is made of?
1. 1.105 x 108 Pa
2. a) 343.9 Pa b) 887.1 N
3. 0.305 N down
4. 27.55 m/s
5. 990 m
6. 2.29 x 106 N
7. 1.5ρA =ρB or Fluid A is 2/3 as dense as Fluid B
8. a) Q1 = 2.75 m3/s b) 1.375 m/s
9. 2.36 m/s2
10. Nothing
11. 7.93 x 10-5 m3
12. 3.79 x 10-8 m3 or 0.039cm3
13. 4 x 10-6 m or 0.004 mm
14. 2.85 m
15. Not Gold (maybe copper lead alloy?) ρ= 9824 kg/m3