Energy
Efficiency
While
transmitting power or changing energy from one form to another,part
of the power or energy is lost due to friction, radiation,
etc. Hence, the
out put is always lesser than the input. As such, energy efficiency
is measured as ;-
Efficiency
= out put of work / input of work
Example
: 100 Revolutions of the handle are required to raise a load
of 1000 kgf to a height of 5 m. Calculate the efficiency.

Output
work = G x h = 1000 kgf x 5 m = 5000 kgfm
Input work = F x S = 20kgf x pi x 1m x 100 = 6280 kgfm
Efficiency = 5000/6280 = 0.8 = 80%
|