Chapter 14: Fluids and Elasticity

A 70 kg mountain climber dangling in a crevasse stretches a 50-m-long, 1.0-cm-diameter rope by 8.0 cm. What is Young’s modulus for the rope?

An 80-cm-long, 1.0-mm-diameter steel guitar string must be tightened to a tension of 2000 N by turning the tuning screws. By how much is the string stretched?

A 3.0-m-tall, 50-cm-diameter concrete column supports a 200,000 kg load. By how much is the column compressed?

A. What is the pressure at a depth of $5000m$in the ocean?

B. What is the fractional volume change $∆V/V$of seawater at this pressure?

C. What is the density of seawater at this pressure?

A large 10,000 L aquarium is supported by four wood posts (Douglas fir) at the corners. Each post has a square 4.0 cm * 4.0 cm cross-section and is 80 cm tall. By how much is each post compressed by the weight of the aquarium?

A 5.0-m-diameter solid aluminum sphere is launched into space. By how much does its diameter increase? Give your answer in mm.

A. In FIGURE $P14.38$, how much force does the fluid exert on the end of the cylinder at$A$?

B. How much force does the fluid exert on the end of the cylinder at $B$?

The two $60$-$cm$-diameter cylinders in FIGURE $P14.39$, closed at one end, open at the other, are joined to form a single cylinder, then the air inside is removed.

A. How much force does the atmosphere exert on the flat end of each cylinder?

B. Suppose one cylinder is bolted to a sturdy ceiling. How many $100kg$football players would need to hang from the lower cylinder to pull the two cylinders apart?

A 6.0 m * 12.0 m swimming pool slopes linearly from a 1.0 m depth at one end to a 3.0 m depth at the other. What is the mass of water in the pool?

FIGURE Q14.4 shows two rectangular tanks, A and B, full of water. They have equal depths and equal thicknesses (the dimension into the page) but different widths.

a. Compare the forces the water exerts on the bottoms of the tanks. Is F_A larger than, smaller than, or equal to F_B? Explain.
b. Compare the forces the water exerts on the sides of the tanks. Is F_A larger than, smaller than, or equal to F_B? Explain.