Torque Calculator from Power and RPM

Torque Formula:

\[ T = \frac{P_w \times 60}{RPM \times 2\pi} \]

Torque (T): lb-ft

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1. What is a Torque Calculator from Power and RPM?

Definition: This calculator estimates the torque produced by a rotating system based on its power output and rotational speed.

Purpose: It helps engineers, mechanics, and technicians determine the torque generated by motors, engines, or other rotating machinery.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ T = \frac{P_w \times 60}{RPM \times 2\pi} \]

Where:

\( T \) — Torque (pound-feet)
\( P_w \) — Power (watts)
\( RPM \) — Rotational speed (revolutions per minute)

Explanation: The formula converts power (energy per unit time) to torque (rotational force) by accounting for the rotational speed.

3. Importance of Torque Calculation

Details: Torque measurement is crucial for designing mechanical systems, selecting appropriate motors, and ensuring proper power transmission.

4. Using the Calculator

Tips: Enter the power in watts and rotational speed in RPM. Both values must be greater than 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is 60 in the numerator?
A: The 60 converts seconds to minutes since power is in watts (joules/second) and RPM is in minutes.

Q2: What's the relationship between torque and power?
A: Power is the rate of doing work, while torque is the rotational force. Power = Torque × Angular Velocity.

Q3: Can I use horsepower instead of watts?
A: Yes, but you'll need to convert horsepower to watts first (1 hp = 745.7 watts).

Q4: Why is the result in pound-feet?
A: This is a common unit for torque in mechanical systems. 1 N·m = 0.7376 lb·ft.

Q5: Does this account for efficiency losses?
A: No, this calculates theoretical torque. Actual torque may be lower due to friction and other losses.