# Torque - to overcome rolling resistance

## Description

Torque, is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist to an object.

“Applied torque” may either be driving torque applied by a motor (often through a transmission) or a braking torque applied by brakes(including regenerative braking). Such torques results in energy dissipation (above that due to the basic rolling resistance of a freely rolling, non-driven, non-braked wheel). This additional loss is in part due to the fact that there is some slipping of the wheel, and for pneumatic tires, there is more flexing of the sidewalls due to the torque. Slip is defined such that a 2% slip means that the circumferential speed of the driving wheel exceeds the speed of the vehicle by 2%.

It is noteworthy that Vs/Ω is usually not equal to the radius of the rolling body.

Related formulas## Variables

T | driving torque (N*m) |

V_{s} | linear speed of the body (at the axle) (m/s) |

Ω | rotational speed (1/s) |

R_{r} | rolling resistance (N) |