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Horsepower Formula:
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The horsepower formula calculates power output from torque and rotational speed (RPM). It's a fundamental equation in mechanical engineering used to determine engine performance and power transmission capabilities.
The calculator uses the horsepower formula:
Where:
Note: The constant 5252 comes from the relationship between rotational speed and power, where 1 horsepower is defined as 550 foot-pounds per second.
Details: Horsepower calculation is essential for evaluating engine performance, comparing different engines, designing mechanical systems, and determining vehicle capabilities. It helps engineers and mechanics understand how much work an engine can perform over time.
Tips: Enter torque in Newton-meters (Nm) and RPM values. The calculator automatically converts Nm to lb-ft before performing the calculation. All values must be positive numbers.
Q1: Why is there a constant 5252 in the formula?
A: The number 5252 comes from the conversion between rotational speed and power (550 ft-lb/sec × 60 seconds ÷ 2π radians).
Q2: What's the difference between torque and horsepower?
A: Torque is a measure of rotational force, while horsepower is a measure of power (work done over time). Horsepower takes into account both torque and how fast that torque is being applied.
Q3: At what RPM does torque equal horsepower?
A: Torque and horsepower are numerically equal at 5252 RPM due to the formula's constant.
Q4: Why convert Nm to lb-ft for this calculation?
A: The standard horsepower formula uses lb-ft as the torque unit. Since Nm is a common metric unit, we convert it to maintain formula accuracy.
Q5: Can I use this calculator for electric motors?
A: Yes, the formula works for any rotating machinery including electric motors, internal combustion engines, and turbines.