The Prehistory of Jazz. The Africanization of American Music. An elderly black man sits astride a large cylindrical drum. Using his fingers and the edge of his hand, he jabs repeatedly at the drum head--which is around a foot in diameter and probably made from an animal skin--evoking a throbbing pulsation with rapid, sharp strokes.
nope, efficiency o fa machine cannot be greater than 100%...theoretically it shows sometime that efficiency of a machine can be 100%, but practically it cannot be possible as â¦ there is some loss of energy is always involved in different ways. Answer   In order for a machine to be 100% efficient, the amount of energy going into it has to be precisely equal to the energy the machine is putting out-with nothing lost.
However, during the last fifty years, continuous enginee ring development work has pushed. the thermal efficiency (18% for the 1939 Neuchatel gas turbine) to present levels of about. 40% for simple cycle operation, and about 55% for combined cycle operation (see below).