Hello Folks, How would I estimate the energy required for machine parts, such as turning a valve? we're talking joules? aye? could i estimate it fairly accurate? any help as to what equations and tools i would use? im basically wanting to measure the efficiency of a machine... the energy put in, and the energy product put out, that would mean i have to measure all the "negative work?!" put about from the begining-through cog to cog-to the end.....where to start?