Summary

• Pressure in a fluid
• Pascal's principle
• Archimedes' principle

• Reading Quiz



• Archimedes' principle
• Practice questions

Example #1

Example #2

Example #3

Example #4

Example #5

Example #6

Example #7

Example #8



• Flow rate and continuity
  Example #9
  
  
• Bernoulli's principle
  Example #10
  
• Bernoulli's equation
  Example #11
  
  Example #12
  
  
• Lift on an aircraft: NASA web site and applet
  
  
• Interactive Example 15-4
• Interactive Example 15-9

Walker4e
Reading quiz Prairie dogs build one entrance of their tunnel higher than the other because the wind speed is higher with increasing altitude. This causes _____ pressure at the high entrance when compared with the low entrance.
A. a higher
B. a lower
C. the same
D. an oscillating
Answer















 
What is the buoyant force on a submerged anchor that has a volume of 0.500 m³?
A. 4900 N
B. 490 N
C. zero
D. Need anchor's density
Answer















 
A block of wood, density 0.45 g/cm³, floats in water. If it is a cube measuring 10 cm on a side, what is its mass?
A. 0.0045 kg
B. 0.045 kg
C. 0.45 kg
D. 4.5 kg
Answer















 
What is the net force on the block of wood?
A. zero
B. 4.50 N
C. 450 N
D. 22.2 N
Answer















 
What is the buoyant force on the block?
A. zero
B. 4.41 N
C. 441 N
D. 21.8 N
Answer















 
What is the weight of the displaced water?
A. 441 N
B. 21.8 N
C. 3.50 N
D. 4.41 N
Answer















 
What is the volume of the displaced water?
A. 4.50 cm³
B. 450 cm³
C. 22.2 cm³
D. 0.00222 cm³
Answer















 
How deep does the block sink into the water?
A. zero cm
B. 4.5 cm
C. 5.5 cm
D. 10 cm
Answer
















A box is 8 cm wide, 10 cm long, and 3 cm high. If it has a mass of 160 g, how deep will it sink into the water?
A. 0.67 cm
B. 1.00 cm
C. 1.50 cm
D. 2.00 cm
Answer















sb5 15.33b
A 2.00 cm diameter hose carries water at 1.06 m/s. With what speed does the water exit a 1.00 cm diameter nozzle?
A. 1.06 m/s
B. 2.12 m/s
C. 4.24 m/s
D. 0.265 m/s
Answer















kw4 tb
Which of the following is NOT due to the Bernoulli effect?
A. Roof removal by hurricane winds.
B. The rising of a hot air balloon.
C. The lift produced on airplane wings.
D. The curved motion of a baseball pitch.
Answer















sj6 14.53
A 2.0 N force pushes a syringe plunger of cross-sectional area A = 25 mm² and forces water out an a = 0.010 mm² needle. What is the speed of the exiting water?
A. 12.6 m/s
B. 9.33 m/s
C. 160 m/s
D. 58.2 m/s

Answer















sj6 ex14.10
A hole is punched at height h in the side of a container of water full to depth h₀. What should h be to maximize the horizontal range?
A. h₀
B. h₀/2
C. h₀/3
D. h₀/4
Answer























 



B. a lower

Bernoulli's principle states that the pressure is least where the speed is greatest. Therefore, the pressure at the higher entrance, where the wind speed is greatest, is lower than the pressure at the entrance at the low end. Fresh air is drawn into the low end of the tunnel and out the high end.
























 



A. 4900 N





















 



C. 0.45 kg





















 



A. zero
By Newton's Second Law, since it is not accelerating.




















 



B. 4.41 N





















 



D. 4.41 N
By Archimedes' principle the weight of the displaced water equals the buoyant force.




















 



B. 450 cm³





















 



B. 4.5 cm





















 



D. 2.00 cm





















 



C. 4.24 m/s





















 



B. The rising of a hot air balloon.
Hot air balloons rise due to Archimedes' principle.




















 



A. 12.6 m/s





















 



B. h₀/2