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# where did go wrong?

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1.  Junior Member Pro Subscriber
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Reputation ## where did go wrong?

24. A motor is operating at 3450 RPM and is producing a torque of 32 lb-in. What is the output horsepower of the motor?
Help: HP = Torque x RPM ÷ 5252 2.  Junior Member
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Reputation ## Units Originally Posted by tlktomegoose 24. A motor is operating at 3450 RPM and is producing a torque of 32 lb-in. What is the output horsepower of the motor?
Help: HP = Torque x RPM ÷ 5252
It says lb-in. Your formula is for lb-ft. 3.  Junior Member Pro Subscriber
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Reputation  Originally Posted by GrayTard It says lb-in. Your formula is for lb-ft.
So to convert lbs per inch to lbs per foot is to multiply by 12 which is 384. Which throws my number way off. 4.  Junior Member
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Reputation  Originally Posted by tlktomegoose So to convert lbs per inch to lbs per foot is to multiply by 12 which is 384. Which throws my number way off.
Your conversion is incorrect. Torque isn't measured in pounds per foot (lb/ft). It's measured in pound-foot (lb-ft), which is a concurrent unit, not reciprocal. So, to do the conversion correctly, you would need to divide your initial torque value by 12, not multiply. 5.  Junior Member Pro Subscriber
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Reputation  Originally Posted by Feyadin Your conversion is incorrect. Torque isn't measured in pounds per foot (lb/ft). It's measured in pound-foot (lb-ft), which is a concurrent unit, not reciprocal. So, to do the conversion correctly, you would need to divide your initial torque value by 12, not multiply.
Awesome! Thank you for the clarity.  