Electric motor with wet type brake and wet type clutch

To provide a motor, a wet type brake, or a wet type clutch in which liquid coolant is sealed and viscous resistance in a gap between a casing and a rotor is reduced. Provided is a motor (10) which includes a casing (60), and a rotor shaft (70) which rotates relative to the casing (60), in which liquid coolant is sealed in the casing (60), and a concave portion (62) is formed on a facing surface (60B) of the casing (60), which faces a rotor (66).