Question

The pressure exerted by a certain liquid at a given point varies directly as the depth of the point beneath the surface of the liquid. The pressure at 70 feet is 350 pounds per square inch. What is the pressure at 30 feet?

a) 150 pounds per square inch

b) 175 pounds per square inch

c) 200 pounds per square inch

d) 225 pounds per square inch

Answer 1

Using direct variation to find pressure at different depths, the pressure at 30 feet is calculated to be 150 pounds per square inch, given that the pressure at 70 feet is 350 pounds per square inch.

Step-by-step explanation:

The question is about calculating the pressure exerted by a liquid at different depths when the pressure at a certain depth is known, and the fact that pressure varies directly with depth. Given that the pressure at 70 feet is 350 pounds per square inch, we can use direct variation to find the pressure at 30 feet. Since the pressure varies directly with the depth, we can write the relationship as P1 / D1 = P2 / D2, where P1 is the pressure at depth D1, and P2 is the pressure we're trying to find at depth D2.

Inserting the known values, we get 350 psi / 70 ft = P2 / 30 ft. Solving for P2 gives us 5 psi/ft * 30 ft = 150 psi. Therefore, the pressure at 30 feet is 150 pounds per square inch.