A rotor blade for a turbomachine, in particular in an aircraft engine, with a cooling arrangement for cooling a surface inside the rotor blade by means of a cooling medium, in particular cooling air. The rotor blade having an impingement cooling device with a plurality of impingement cooling openings for deflecting the cooling medium flowing in the interior of the impingement cooling device onto the surface that is to be cooled by means of impingement cooling inside the rotor blade and that is located outside of the impingement cooling device, so that the surface can be cooled by means of an impingement cooling through a cooling medium than exits from the impingement cooling openings, wherein the impingement cooling device is movably mounted with respect to the rotor blade.