SOLUTION: The horsepower (hp) that a shaft can safely transmit varies jointly with its speed (in revolutions per minute rpm) and the cube of its diameter. If the shaft of a certain material

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Question 499660: The horsepower (hp) that a shaft can safely transmit varies jointly with its speed (in revolutions per minute rpm) and the cube of its diameter. If the shaft of a certain material 2 inches in diameter can transmit 36 hp at 75 rpm, what diameter must the shaft have in order to transmit 14 hp at 30 rpm?
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
The horsepower (hp) that a shaft can safely transmit varies jointly with its speed (in revolutions per minute rpm) and the cube of its diameter. If the shaft of a certain material 2 inches in diameter can transmit 36 hp at 75 rpm, what diameter must the shaft have in order to transmit 14 hp at 30 rpm?
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hp = k*rpm*d^3
36 = k*75*8
k = 36/600 = 0.06
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14 = 0.06*30*d^3 = 1.8d^3
d^3 = 14/1.8
d =~ 1.981 inches