Physics
Torque from a force at right angles
Force in newtons times the perpendicular distance from the pivot, in metres. The result is in newton metres.
The Formula
tau = F x r
Force in newtons times the perpendicular distance from the pivot, in metres. The result is in newton metres.
| Symbol | Meaning | Unit | Notes |
|---|---|---|---|
| tau | Torque | newton metres | Turning effect about the pivot. |
| F | Force | newtons | Force applied, perpendicular to the lever arm. |
| r | Lever arm | metres | Perpendicular distance from pivot to the line of the force. |
What Each Symbol Means
taunewton metres
Torque
Turning effect about the pivot.
Fnewtons
Force
Force applied, perpendicular to the lever arm.
rmetres
Lever arm
Perpendicular distance from pivot to the line of the force.
See It Worked With Real Numbers
A formula on its own does not tell you which number goes where. The how to calculate torque page applies this equation to a concrete case, shows every intermediate step, and names the mistakes that produce a wrong answer even when the algebra is right.
Where This Formula Appears
This equation is the working core of How To Calculate Torque, filed under Science. Every number the guide produces comes from substituting into this one line.