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explain y d efficiency of a machine is always less than 100%?
Because some of the works done is used to overcome friction.whats my reward liquidstar1000
The mechanical efficiency of a machine is always less than 100% because some energy is lost as heat in friction.
In simple machine, efficiency is defined as Mechanical Advantage divided by Velocity Ratio (Efficiency= MA/VR ).
Gasoline Engine may have a thermal efficiency of only 25% and steam engine may have just 10%.
When the machine is a heat engine, the theoretical thermal efficiency can be found from the 2nd law of thermodynamics, but the values are always lower.
The only machine with 100% efficiency is the carnot engine, which does not exist practically.
In any machine there is a
way to put the energy inside
and there is a way to take
the energy out.The out put
energy need not be the same
type of input energy.
In any machine as per
conservation of energy the
input and out put energies
must be equal.
But what we speak of
efficiency of a machine is the
ratio of the useful out put
energy to the input energy.
Naturally this will be less
than the total out put energy.
It follows efficiency is less
But we can try our best to
reduce the unused energy
(not used for our purpose)to
be the minimum possible.
For example in machines due
to friction many energy is
being lost as the parts are
heated. But with out friction
no parts will work. So some
minimum amount of energy
has to be wasted (wasted
according to us and not
according to nature).
A car rolls down the road
because of friction and the
same friction reduces
Nice job Spottykay, but you really sound like an amatuer physicist LOL!
i'm not much Good in science
@Sir-Phil, that carnot machine is not practicable; so it doesnt prove 100% efficiency.
Yeah if you got me correctly, I said it doesnt exist in practical sense though, it is believed to be the only machine with 100% efficiency
Alright; I can get you.
Am glad you have.
whats the meaning of carnot engine
It has been well explained. Bother to scroll up and you wont be asking any questions.
i mean what does the machine does
I clearly stated that it does not exist in practical sense. Though it is believed to have 100% Efficiency
@Spottykay, its just like the believe of existence of dragon, which breathe fire out of his mouth; but have you seen such an animal before?
Exactly, its merely an assumption. Its not feasible
ah i cant see it and cant wait for it but i can snap it
O Yes, that is how the case of Carnot engine is.