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Torque to HP Formula:
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The Torque to HP formula calculates horsepower from torque and RPM. This fundamental engineering equation is widely used in automotive, mechanical engineering, and industrial applications to determine engine power output.
The calculator uses the torque to HP formula:
Where:
Explanation: The constant 5252 comes from the relationship between rotational power and linear power, where 1 horsepower equals 550 foot-pounds per second and there are 60 seconds in a minute.
Details: Accurate horsepower calculation is essential for engine performance analysis, vehicle design, mechanical system optimization, and comparing power outputs across different engines and applications.
Tips: Enter torque in pound-feet (lb-ft) and RPM in revolutions per minute. Both values must be positive numbers for accurate calculation.
Q1: Why is the constant 5252 used in the formula?
A: The constant 5252 comes from the conversion between foot-pounds per minute and horsepower, where 1 hp = 33,000 ft-lb/min and 33,000 ÷ (2π) ≈ 5252.
Q2: What are typical torque and RPM values for car engines?
A: Most car engines produce 100-400 lb-ft of torque at 2000-6000 RPM, resulting in 50-500 horsepower depending on the engine size and type.
Q3: Can this formula be used for electric motors?
A: Yes, the formula works for any rotating machinery including electric motors, though electric motors often have different torque-RPM characteristics than internal combustion engines.
Q4: What's the relationship between torque and horsepower?
A: Torque measures rotational force, while horsepower measures work done over time. High torque at low RPM provides good acceleration, while high horsepower at high RPM provides top speed.
Q5: How accurate is this calculation for real-world applications?
A: The formula provides theoretical mechanical horsepower. Actual wheel horsepower may be lower due to drivetrain losses, typically 15-20% for rear-wheel drive vehicles.