The depth of water behind the Hoover Dam is $220 \mathrm{~m}$. Show that the water pressure at the base of this dam is $2200 \mathrm{kPa}$

Calculate the water pressure at the base of Hoover Dam. The depth of water behind the dam is 220 m. (Neglect the pressure due to the atmosphere.)

Consider an airplane with a total wing surface of $100$ square meters. At a certain speed the difference in the air pressure below and above the wings is $4 \%$ of atmospheric pressure. Show that the lift on the airplane is $400,000 \mathrm{~N}$.

Calculate the pressure a $10 \mathrm{~N}$ block exerts on the table it rests on if its area of contact is $50 \mathrm{~cm}^2$.

Pressure $=$ weight density $\times$ depth

(Use $10,000 \mathrm{~N} / \mathrm{m}^3$ for the weight density of water, and ignore the pressure due to the atmosphere in the calculations below.)

Show that the water pressure at the bottom of the 50 -m-high water tower in the chapter-opening photo is $500,000 \mathrm{~N} / \mathrm{m}^2$, which is approximately $500 \mathrm{kPa}$

Water in the lake behind Hoover Dam is 221 m deep. What is the water pressure at the base of the dam?

What happens to the air pressure inside a balloon when the balloon is squeezed to half its volume at constant temperature?

By how much does the density of air increase when it is compressed to half its volume?

An airplane has a total wing surface of 200 square meters. The airplane requires a lift of $500,000 \mathrm{~N}$ to take off. What should be the difference in the air pressure between the bottom and top surface of the wings to produce this lift?

Rank the buoyant force supplied by the atmosphere on the following, from greatest to least: (a) an elephant, (b) a helium-filled party balloon, and (c) a skydiver at terminal velocity.

What happens to the air pressure inside a balloon when it is squeezed to half its volume at constant temperature?

Distinguish between force and pressure. Compare their units of measurement.

Suppose that you balance a 5-kg ball on the tip of your finger, which has an area of $1 {cm^2$. Show that the pressure on your finger is$49 {N} / {cm}^2$, which is$490 {kPa}$.

Give two examples of a fluid.