Fluid Mechanics Practice Problems for AP Physics B & C
Review the following concepts if necessary:
- Fluid Mechanics for AP Physics B
- Buoyancy and Archimedes' Principle for AP Physics B
- Pascal's Principle for AP Physics B
- Flowing Fluids for AP Physics B
- A person sips a drink through a straw. At which of the following three positions is the pressure lowest?
- Inside the person's mouth
- At the surface of the drink
- At the bottom of the drink
- only at position I
- only at position II
- only at position III
- both at positions I and III
- both at positions I and II
- The circulatory system can be modeled as an interconnected network of flexible pipes (the arteries and veins) through which a pump (the heart) causes blood to flow. Which of the following actions, while keeping all other aspects of the system the same, would NOT cause the velocity of the blood to increase inside a vein?
- expanding the vein's diameter
- cutting off blood flow to some other area of the body
- increasing the heart rate
- increasing the total amount of blood in the circulatory system
- increasing the pressure difference between ends of the vein
- A pirate ship hides out in a small inshore lake. It carries twenty ill-gotten treasure chests in its hold. But lo, on the horizon the lookout spies a gunboat. To get away, the pirate captain orders the heavy treasure chests jettisoned. The chests sink to the lake bottom. What happens to the water level of the lake?
- The water level drops.
- The water level rises.
- The water level does not change.
- Brian saves 2-liter soda bottles so that he can construct a raft and float out onto Haverford College's Duck Pond. If Brian has a mass of 80 kg, what minimum number of bottles is necessary to support him? The density of water is 1000 kg/m3, and 1000 L = 1 m3.
- 1600 bottles
- 800 bottles
- 200 bottles
- 40 bottles
- 4 bottles
- The water tower in the drawing above is drained by a pipe that extends to the ground. The amount of water in the top spherical portion of the tank is significantly greater than the amount of water in the supporting column.
- What is the absolute pressure at the position of the valve if the valve is closed, assuming that the top surface of the water at point P is at atmospheric pressure?
- Now the valve is opened; thus, the pressure at the valve is forced to be atmospheric pressure. What is the speed of the water past the valve?
- Assuming that the radius of the circular valve opening is 10 cm, find the volume flow rate out of the valve.
- Considering that virtually all of the water is originally contained in the top spherical portion of the tank, estimate the initial volume of water contained by the water tower. Explain your reasoning thoroughly.
- Estimate how long it would take to drain the tank completely using this single valve.
Information you may need: Density of water = 1000 kg/m3.