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If the kinetic energy of both molecules, relative to each other, is high enough, their speed will be above "escape velocity". That means the molecular attraction can be ignored, they are gasses, and they will have positive pressure. Zero contraction is possible. This is why they are called...

Contraction on a PV diagram, by definition, would appear as a negative absolute pressure. A value lower than a perfect vacuum. All those links are in the positive pressure segment of a PV diagram, even when below atmospheric pressure. Trying to redefine contraction to any compression that is below a...

Can you show contraction on a PV diagram?

Have you measured contraction on an indicator diagram?

You've measured this "contraction"? Have data showing an internal tensile force? Shown a piston being pulled back when the open end is in space or a vacuum? No sir. You will always see the cork pushed out of a gun in space. Expansion forever no contraction. Do not confuse an atmosphere pus...

MikeB, thanks. I agree totally. Tom, if a horizontal cylinder piston combination at atmospheric temperature and pressure is turned upside down such that the mass of the piston "hangs", the inside working gas will expand pushing the piston outwardly. The gas is outputting work. The atmosphe...

Heat is converted to work at the instant a gas particle impacts the piston and transfers energy to the piston. Internal energy is like a bank account. Pay-Joules/money coming in is like heat. Your balance-Jouels/money saved is like internal energy, in that they are not the same. Internal energy is ...

Harmonic motion is the kinematic engineering term for a motion that purely sinusoidal in time. Since a crank pin describes a circle anything hooked to it will move, more or less, sinusoidally. A sine wave in kinematics is desirable because it's derivative is a cosine, and the derivative of a cosine ...

Work is depicted on a PV diagram by the bases of Work = F•d, Force times distance. Where pressure is the force and change in volume is the distance. For every pebble removed by rolling it off onto a hill, of the same height preserving their potential energy, the rest of the pebbles are lifted higher...

You seem to accept isothermal lines on a PV diagram? No temperature represented, yet you seem to accept them.

What other lines do you accept?
Constant pressure, horizontal?
Constant volume, vertical?
Adiabatic lines, similar but steeper to the isotherms.

Do you accept

Work = P•(V2--V1) = P•∆V

Do accept what that looks like on a PV diagram?

A change in V equates to an area under the path equivalent to work.

During a conventional discussion of heat engines it is customary to break a PV diagram into four idealized processes. That's for the ease of seeing and explaining what happens for each and the whole cycle. Real engines mimic those ideal processes, but for the most part are not all that close. So, le...

The desire not to poo poo an idea, squelch enthusiasm, is in opposition to the desire to point out an obvious fraud. That conundrum makes us open to compassion and deception. Don't let yourself be deluded into believing in, something impossible, just because a promotion is appealing and not fully ex...

Can you accept that, on a PV diagram, motion to the right, increasing volume, is work output? Can you also accept the reverse, that motion to the left, decreasing volume, is work input? For both, we are limiting description to the working gas. The gas is doing work > output. Or work is being input t...

It appears we have already seen how both, adding load and adding heat, appears on a PV diagram. The load slows down the engine. The PV diagram fattens growing upwards and downwards. Producing a larger output of work per cycle. It is readable as a larger area enclosed by the cycle's path. It also sho...

One could always get a bunch of aluminum oxide sand blast media and stick it together with a small amount of sodium silicate (water glass). Tim Tinker has done this. Aluminum oxide melts at a much higher temperature than quartz glass. It is also known as sapphire or porcelain. Sapphire is one of the...