1. What is the Horsepower Formula?

The horsepower formula calculates power output from torque and rotational speed (RPM), taking into account any gear ratio. It's fundamental in automotive and mechanical engineering applications.

2. How Does the Calculator Work?

The calculator uses the horsepower formula:

Where:

• \( Torque \) — Rotational force (lb-ft)
• \( Ratio \) — Gear ratio (decimal)
• \( RPM \) — Revolutions per minute
• 5252 — Conversion constant (derived from the relationship between horsepower, torque, and RPM)

Explanation: The formula shows that horsepower is directly proportional to both torque and RPM, with the gear ratio modifying the effective torque.

3. Importance of Horsepower Calculation

Details: Accurate horsepower calculation is crucial for engine performance analysis, vehicle design, and mechanical system optimization.

4. Using the Calculator

Tips: Enter torque in lb-ft, ratio as a decimal (e.g., 3.73), and RPM in revolutions per minute. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Why is 5252 the conversion constant?
A: 5252 comes from the relationship between rotational speed and power (1 horsepower = 550 ft-lb/sec, and there are 2π radians in a revolution).

Q2: What's the difference between wheel horsepower and engine horsepower?
A: Wheel horsepower accounts for drivetrain losses, while engine horsepower is measured at the crankshaft. This calculator gives engine-equivalent HP.

Q3: How does gear ratio affect horsepower?
A: Gear ratio multiplies torque but divides speed - the power remains the same (minus efficiency losses), but this calculator shows the effective power at a given RPM.

Q4: Can I use this for electric motors?
A: Yes, the formula works for any rotating machinery, though electric motors often have different torque curves than combustion engines.

Q5: What's a typical horsepower range for cars?
A: Compact cars: 100-200 hp, midsize: 150-300 hp, performance cars: 300-700 hp, supercars: 500-1000+ hp.