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.
For example, if you put 100 Joules of energy into a machine, and got 50 Joules back out (and the other 50 Joules was wasted by the machine), you would have 50% efficiency. You can calculate percent efficiency by taking how much energy you got out, dividing it by how much you started with, and multiplying by 100%.y physics teacher wants us to calculate the efficiency of out catapults. she gave us a formula, but it doesn't work. The mass of the tennis ball we are launching is 57g, and the horizontal distance it traveled is 16 meters. The length of the arm is .6 meters (2 feet).