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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 and automotive applications to measure engine performance.
The calculator uses the horsepower formula:
Where:
Explanation: The formula shows that horsepower is directly proportional to both torque and RPM. The constant 5252 comes from the fact that 1 horsepower is defined as 550 foot-pounds per second, and there are 2π radians in one revolution.
Details: Horsepower is a crucial metric for evaluating engine performance, comparing vehicles, and designing mechanical systems. It helps determine a vehicle's acceleration, towing capacity, and overall power output.
Tips: Enter torque in pound-feet (lb-ft) and RPM in revolutions per minute. Both values must be positive numbers. The calculator will compute the horsepower instantly.
Q1: Why is 5252 the magic number in the formula?
A: It's the RPM at which torque and horsepower values are equal (when plotted on the same scale). This comes from the unit conversions between rotational speed and power.
Q2: What's the difference between horsepower and torque?
A: Torque measures rotational force, while horsepower measures the rate at which work is done (power). Torque gets things moving, horsepower keeps them moving at speed.
Q3: How does RPM affect horsepower?
A: Generally, horsepower increases with RPM up to a point, then may decrease as engine efficiency drops at very high RPMs.
Q4: What's a typical horsepower range for cars?
A: Compact cars: 100-200 hp, midsize: 150-300 hp, performance cars: 300-700+ hp. Electric vehicles often have higher horsepower ratings.
Q5: Can I use this for electric motors?
A: Yes, the formula works for any rotational power system, including electric motors, though electric motors often have different torque curves than combustion engines.