Calculating Torque From HP

Torque Formula:

\[ T = \frac{HP \times 5252}{RPM} \]

Torque (T):

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1. What is the Torque Formula?

The torque formula calculates rotational force from horsepower and RPM. It's a fundamental equation in mechanical engineering that helps determine the twisting force an engine or motor can produce at a given rotational speed.

2. How Does the Calculator Work?

The calculator uses the torque formula:

\[ T = \frac{HP \times 5252}{RPM} \]

Where:

\( T \) — Torque (lb-ft)
\( HP \) — Horsepower (hp)
\( RPM \) — Revolutions per minute
5252 — Conversion constant (derived from the relationship between rotational speed and power)

Explanation: The constant 5252 comes from the fact that one horsepower is defined as 550 foot-pounds per second, and there are 2π radians in one revolution.

3. Importance of Torque Calculation

Details: Torque calculation is essential for engine performance analysis, vehicle design, mechanical system optimization, and understanding the power characteristics of rotating machinery.

4. Using the Calculator

Tips: Enter horsepower in hp and RPM in revolutions per minute. Both values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: Why is the constant 5252 used in the formula?
A: The constant 5252 comes from the conversion between rotational power and linear power (1 hp = 550 ft-lb/s and 1 rpm = 2π/60 rad/s).

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 = (Torque × RPM) / 5252.

Q3: Can this formula be used for electric motors?
A: Yes, the formula works for any rotating machinery, including electric motors, internal combustion engines, and turbines.

Q4: What are typical torque values for different engines?
A: Torque values vary widely: small car engines might produce 100-200 lb-ft, while large diesel engines can produce over 1000 lb-ft of torque.

Q5: How does torque relate to vehicle performance?
A: Torque determines acceleration and pulling power, while horsepower relates to top speed. High torque at low RPM is good for towing and quick acceleration.