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Hunter-Best [27]

2 years ago

15

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. A b

oat with a wet surface area of 83 ft 2 traveling at 20 mph experiences a drag force of 996 N . Find the wet surface area of a boat traveling 18 mph and experiencing a drag force of 1215 N .

1 answer:

Advocard [28]2 years ago

7 0

Answer:

Wet surfaces areaA=+25.3ft^2

Explanation:

Using F= K×A× S^2

Where F= drag force

A= surface area

S= speed

Given : F=996N S=20mph A= 83ft^2

K = F/AS^2=996/(83×20^2)

K= 996/33200 = 0.03

1215= (0.03)× A × 18^2

1215=9.7A

A=1215/9.7=125.3ft^2

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The figure is missing: find it in attachment.

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