Calculate Torque From Horsepower And RPM

Torque Formula:

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

Torque (T):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Torque?

Torque is a measure of the rotational force applied to an object. In automotive and mechanical engineering, torque represents the twisting force that causes rotation, measured in foot-pounds (ft-lb) or Newton-meters (Nm).

2. How Does the Calculator Work?

The calculator uses the torque formula:

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

Where:

\( T \) — Torque in foot-pounds (ft-lb)
\( HP \) — Horsepower
\( RPM \) — Revolutions per minute
\( 5252 \) — Conversion constant derived from the relationship between horsepower, torque, and RPM

Explanation: The constant 5252 comes from the fact that one horsepower is defined as 550 foot-pounds per second, and there are 60 seconds in a minute (550 × 60 ÷ 2π ≈ 5252).

3. Importance of Torque Calculation

Details: Torque calculation is essential for understanding engine performance, vehicle acceleration, towing capacity, and mechanical system design. It helps engineers optimize power delivery and efficiency.

4. Using the Calculator

Tips: Enter horsepower and RPM values. Both values must be positive numbers. The calculator will compute the corresponding torque in foot-pounds.

5. Frequently Asked Questions (FAQ)

Q1: Why is the constant 5252 used in the formula?
A: The constant 5252 comes from the conversion between horsepower and torque, where 1 HP = 550 ft-lb/sec and there are 60 seconds in a minute (550 × 60 ÷ 2π ≈ 5252).

Q2: What is the relationship between horsepower and torque?
A: Horsepower is a measure of work done over time, while torque is a measure of rotational force. Horsepower = (Torque × RPM) ÷ 5252.

Q3: At what RPM does horsepower equal torque?
A: Horsepower and torque are numerically equal at 5252 RPM, as evident from the formula.

Q4: Can this formula be used for electric motors?
A: Yes, the formula applies to any rotating machinery, including electric motors, internal combustion engines, and turbines.

Q5: How accurate is this calculation?
A: The calculation is mathematically exact for the given inputs. However, real-world mechanical systems may have efficiency losses not accounted for in this basic formula.