Mi-12 Torque


To demonstrate that Torque is a rotational force. The required force applied to a lever can be greatly reduced the further away you apply it from the hinge point.


  • 1m Ruler with holes
  • Spring Balance
  • Retort Stand
  • Small Rod



The meter rule is suspended on a small rod at the origin (0cm) and is free to rotate as shown in the diagram. A series of holes have been drilled at the 0,10,20,50,80&100cm on the ruler, so a spring balance can be used to suspend the ruler horizontally. The force required to suspend the ruler horizontally can be measured.

Torque τ is given by the equation


By suspending the ruler horizontally along the various holes using the spring balance. The Torque τ (Nm) should be the same value no matter where the spring balance is placed along the ruler. The force required to suspend the ruler horizontally reduces the further away from the hinge point.