Torque Calculator Formula

Understand the math behind the torque calculator. Each variable explained with a worked example.

Formulas Used

Torque

torque = force * radius * sin(angle_rad)

Variables

VariableDescriptionDefault
forceApplied Force(N)50
radiusLever Arm Distance(m)0.3
angleAngle Between Force and Lever(degrees)90
angle_radDerived value= angle * pi / 180calculated

How It Works

Torque (Moment of Force)

Torque measures the tendency of a force to cause rotation about an axis.

Formula

tau = F * r * sin(theta)

Maximum torque occurs when the force is perpendicular to the lever arm (theta = 90 degrees).

Worked Example

A 50 N force is applied perpendicular to a 0.3 m wrench.

force = 50radius = 0.3angle = 90
  1. 01tau = F * r * sin(theta)
  2. 02tau = 50 * 0.3 * sin(90°)
  3. 03tau = 50 * 0.3 * 1
  4. 04tau = 15 N·m

Frequently Asked Questions

What is the unit of torque?

In SI, torque is measured in newton-meters (N·m). Although dimensionally identical to joules, torque is not energy.

When is torque maximized?

Torque is maximized when the force is applied perpendicular to the lever arm (theta = 90°), because sin(90°) = 1.

How does torque relate to angular acceleration?

By Newton's second law for rotation: tau = I * alpha, where I is moment of inertia and alpha is angular acceleration.

Learn More

Guide

How to Calculate Torque: Formulas, Units, and Real-World Applications

Master torque calculations for engineering applications. Covers torque formulas, moment arms, units conversion, motor torque, bolt torque, and the relationship between torque, speed, and power.

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