Possible violation of the Kelvin statement (2nd law)?

[weezy]

Say I have an infinite cylinder filled with monoatomic gas and on one end has a piston attached to it. I now supply heat to the cylinder. The gas expands thereby converting all of heat energy into physical work(displacement of the piston). Since the cylinder is very long it eliminates the requirement of a cyclic process and could in theory provide work for a very long time until the piston reaches the cylinder's length. Have I not just violated kelvins statement? Provided friction is zero? W=P.dV?

 

[mfb]

Why bother heating it? You have an infinite amount of energy stored in your cylinder, you can easily extract a finite amount out of it without changing the system.
Working with infinite things just doesn't work.

 

[weezy]

Why bother heating it? You have an infinite amount of energy stored in your cylinder, you can easily extract a finite amount out of it without changing the system.
Working with infinite things just doesn't work.

What if it was very long but finite? Wouldn't then all the Q I supply be converted to work?

 

[mfb]

If you have an infinite vacuum of zero temperature available, and infinite time for the process.

 

[DuckAmuck]

How are you supplying heat though? A flame, electricity, a hamster on a wheel? That is where the increase in entropy is occurring here.

 

[weezy]

How are you supplying heat though? A flame, electricity, a hamster on a wheel? That is where the increase in entropy is occurring here.

I still haven't been exposed to the idea of entropy yet. Basically I mean that if the cylinder is very long for some finite amount of time I could get all of the heat energy to be expand the gas and thereby converting "all" heat into work.

 

[mfb]

If you have a perfect vacuum (or anything else) at zero temperature as cold reservoir, you can convert heat to mechanical power with an efficiency of (nearly) 100%.