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.
We'll call the latter factor Mold Efficiency, which tells us how well the molding process ran. Machine Efficiency is simple calculation. It is the machine's run time versus available time. So, a machine that was down two hours of an eight-hour shift has a 75% Machine Efficiency. Because Machine Efficiency is easy to calculate and understand, many molders already track it as a critical performance measure. Mold Efficiency is more abstract.