The drag force F on a boat varies jointly with the wet surface area A f the boat and the square of the speed s of the boat. A boat with a wet surface area of 50 ft^2 7 mph traveling atexperiences a drag force of 98n Find the speed of a boat experiencing a drag force of 135 nand having a wet surface area of 60ft^2.

Answer: S = 237.2 mph

Step-by-step explanation:

Given that the drag force F on a boat varies jointly with the wet surface area A of the boat and the square of the speed s of the boat.

That is. F = KAS^2

Where

F = drag force

K = proportionality constant

S = speed

A boat with a wet surface area of 50 ft^2 traveling at 7 mph experiences a drag force of 98N

1 square foot = 3.587*10^-8 square mile

A = 50 * 3.587*10^-8

A = 1.7935*10^-6

Using the derived formula

F = KAS^2

98 = K * 1.7935*10^-6 * 7^2

98 = 8.788x10^-5K

K = 1115.14

To Find the speed of a boat experiencing a drag force of 135 N and having a wet surface area of 60ft^2. We will use the same formula

A = 60 * 3.587*10^-8

A = 2.1522*10^-6

F = KAS^2

135 = 1115.14 * 2.1522*10^-6 * S^2

S^2 = 56249.9

S = 237.2 mph