Energy Losses and Efficiency
Machines lose energy through friction, deformation and wear, which is dissipated as heat. This means the power out of the machine is less than power in. The ratio of power out to power in is the efficiency η of the machine, and is a measure of the energy losses,
The velocity ratio of a machine is fixed by its dimensions, so it is the mechanical advantage that is reduced by the losses, that is
So in non-ideal machines, the mechanical advantage is always less than the velocity ratio by the product with the efficiency η. So a machine that includes losses such as friction, deformation and wear, will not be able to move as large a load as a corresponding ideal machine using the same input force.
The efficiency of a compound machine is the product of the efficiencies of the series of simple machines that form it,
Read more about this topic: Simple Machine
Famous quotes containing the words energy, losses and/or efficiency:
“Perhaps catastrophe is the natural human environment, and even though we spend a good deal of energy trying to get away from it, we are programmed for survival amid catastrophe.”
—Germaine Greer (b. 1939)
“Hold back thy hours, dark Night, till we have done;
The Day will come too soon.
Young maids will curse thee, if thou steal’st away
And leav’st their losses open to the day.
Stay, stay, and hide
The blushes of the bride.”
—Francis Beaumont (1584-1616)
“Nothing comes to pass in nature, which can be set down to a flaw therein; for nature is always the same and everywhere one and the same in her efficiency and power of action; that is, nature’s laws and ordinances whereby all things come to pass and change from one form to another, are everywhere and always; so that there should be one and the same method of understanding the nature of all things whatsoever, namely, through nature’s universal laws and rules.”
—Baruch (Benedict)