A brush for an electric machine includes at least one brush body having an electrical resistance, which is configured to electrically contact at least one component moving relative to the brush body during operation of the electric machine, and which sustains wear during the operation of the electric machine along a wear direction, as a result of friction contact with the component. The brush includes a detection device configured to determine wear of the brush body, where the detection device comprises a plurality of detection zones which are mutually spaced apart along the wear direction, the respective electrical resistance of which differs from the electrical resistance of the brush body.