A large chunk of metal has a mass of $393 \mathrm{~kg}$, and its volume is measured to be $0.05 \mathrm{~m}^3$. (a) Find the metal's mass density and weight density in SI units. (b) What kind of metal is it?

A grain silo is filled with 2 million pounds of wheat. The area of the silo's floor is $400 \mathrm{ft}^2$. Find the pressure on the floor in pounds per square foot and in psi.

A bicycle tire pump has a piston with area $0.44$ in. $^2$. If a person exerts a force of $30 \mathrm{lb}$ on the piston while inflating a tire, what pressure does this produce on the air in the pump?

What substances would sink in gasoline but float in water?

The depth of the Pacific Ocean in the Mariana Trench is $36,198 \mathrm{ft}$. What is the gauge pressure at this depth?

A large truck tire is inflated to a gauge pressure of 80 psi. The total area of one sidewall of the tire is 1,200 in. $^2$. What is the outward force on the sidewall because of the air pressure?

Why does the buoyant force always act upward?

The "suction cup" is a common device used to suspend pictures, plants, and other objects from walls, ceilings, windows, and other smooth surfaces. Why is the name "suction cup" a bit of a misnomer? Is anything really "sucking"? How exactly does a "suction cup" work? Explain.

Would the weight density of water be different on the Moon than it is on Earth? What about the mass density? Explain.

Workers are to install a hatch (door) near the bottom of an empty storage tank. In choosing how strong to make the hatch, does it matter how tall the tank is? How wide it is? Whether it is going to hold water or mercury? Explain.

A brick is tied to a balloon filled with air and then tossed into the ocean. As the balloon is pulled downward by the brick, the buoyant force on it decreases. Why?

At the bow of a ship on a stormy sea, a crewman conducts an experiment by standing on a bathroom scale. In calm waters, the scale reads $182 \mathrm{lb}$. During the storm, the crewman finds a maximum reading of $225 \mathrm{lb}$ and a minimum reading of $138 \mathrm{lb}$. Find the maximum upward acceleration.

The way pressure increases with depth in a gas is different from the way it does in a liquid. Why?

A large tanker truck can carry 20 tons ( $40,000 \mathrm{lb})$ of liquid. (a) What volume of water can it carry? (b) What volume of gasoline can it carry?