Abstract: The process of controlling rotational speed of an electric motor of an electric hand tool, including providing an electric motor of an electric hand tool with a rotational speed control comprised of displacement means for providing displacement in response to manual operation of the electric hand tool selected from the group consisting essentially of a linear displacement device for providing linear displacement (s) and an actuating dial for providing arcuate displacement (S); an elastic membrane to which the displacement means is articulatedly connected so that during displacement of the displacement means the elastic membrane deforms as a function of the displacement; actuating means comprising a sensor element coupled to the elastic membrane so that the sensor element produces an electrical output variable as a function of the deformation of the elastic membrane, the sensor element being selected from the group consisting essentially of a Hall sensor, an inductive sensor, and a sensor switch; and an electr