Answer:
122.5 lbs
Step-by-step explanation:
The relation between force, wind speed, and area can be written ...
f = ks²a
for some wind speed s and area a.
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The constant of proportionality, k, can be found from the given data.
64.8 = k(18²)(500) . . . force in pounds, area in square feet, speed in mph
k = 64.8/(324×500) = 0.0004
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Using the equation with the second set of data, we have ...
f = 0.0004(35²)(250) = 122.5 . . . . pounds
The force on the 250 square foot sail would be 122.5 pounds.
