Is a machine physically possible that has an efficicency greater than 100 percent?

Answer 1

No. In fact, in the real world, a machine with an efficiency of only 100%

isn't even physically possible.

But why isn't an efficiency greater than 100% physically possible ?

Efficiency means (output energy) divided by (input energy) .

If efficiency is greater than 100%, that means output/input is greater than ' 1 ', and

that means that you get more energy out of the machine than you put into it.

Where could that extra energy come from ? Remember the law of conservation

of energy ? It says that energy is never created or destroyed. So you can't get

more energy out of a machine than you put into it, and output/input can't be

more than ' 1 '.

It sure would be nice though: Put some energy into the machine to get it started,

and then just sit back and watch it run. Out of the end comes more energy than

what it takes to run the machine, so you split up the energy that comes out. You

take just enough to keep the machine running, and you put that much back into it.

Then you still have some energy left over, so you take that part and use it to heat

your house, or pump water out of the well, or generate electricity to light your Christmas

lights, or sell it. You'd never need to buy any more energy, or burn any coal or oil or

wood or uranium, because you'd get enough out of the machine to keep it running

plus more energy to use or sell.