Efficiency

EFFICIENCY: A RATIO THAT REPRESENT'S THE AMOUNT OF ENERGY OUTPUT BY A MACHINE TO THE AMOUNT OF INPUT PUT INTO THE MACHINE BY THE USER. to put it into understandable terms, the work output provided by the machine, divided by the work input of the machine multiplied by 100 will give you efficinetcy.The reason you multiply the quotiant by 100 is, in a realistic problem the input will alwayse be greater than the output meaning a decimal answer, such as .75x100= 75%, efficiency will alwayse be described as a percentage or in some cases a ratio. the formula for efficiency is the following : Efficiency %= work output/work input

Here are some sample problems and how you would solve them:

A motorized **machine** requires an input work of 3500 joules to perform an output work of 2700 joules. What is the **efficiency** of the **machine**? so we know eff%=wout/winx100 so eff%= 2700/3500= ? for example this yo-yo if i throw it with 40 joules its output is around 13 joules and even if modified is found impossible to exceed 40 joules A machine requires 450 joules input work and preforms 297 joules of output work, what is the efficiency of the machine? answers: efficiency answers source: ipc book http://www.ecopromogifts.co.uk/downloads/lowres/Miscellaneous%20Accessories/yoyo.jpg