Understanding Torque

Torque is a measure of the force that can cause an object to rotate about an axis. It is a vector quantity, meaning it has both magnitude and direction.

Introduction

Torque, also known as moment of force, is the rotational equivalent of linear force. It describes the tendency of a force to rotate an object around an axis, fulcrum, or pivot point.

History

The concept of torque was developed alongside the understanding of rotational mechanics. Archimedes first described the principle of the lever, which is fundamentally based on torque. The mathematical formulation was refined during the development of classical mechanics by Newton and others.

Key Units

Newton-meter (N⋅m)

The SI unit of torque, representing the torque produced by a force of one newton applied at a perpendicular distance of one meter from the axis.

Pound-force foot (lbf⋅ft)

An imperial unit commonly used in automotive applications, equal to approximately 1.356 N⋅m.

Kilogram-force meter (kgf⋅m)

A metric unit sometimes used in engineering, equal to approximately 9.807 N⋅m.

Applications

  • Automotive engine specifications and wheel lug nut tightening
  • Industrial machinery and motor design
  • Robotics and mechanical arm control
  • Construction and structural engineering
  • Sports equipment design and biomechanics

Torque Calculation

τ = r × F × sin(θ)

Torque (τ) equals the distance from the axis (r) multiplied by the applied force (F) and the sine of the angle (θ) between the force vector and the lever arm.