Recent content by Andrew Mason

I was trying to simplify it a bit further: ##T_f=\frac{(\frac{PV_{A,0}}{RT_{A,0}})C_AT_{A,0}+(\frac{PV_{B,0}}{RT_{B,0}})C_BT_{B.0}}{(\frac{PV_{A,0}}{RT_{A,0}})C_A+(\frac{PV_{B,0}}{RT_{B,0}})C_B}-\frac{k}{2A^2}\frac{(\Delta V)^2}{(\frac{PV_{A,0}}{RT_{A,0}})C_A+(\frac{PV_{B,0}}{RT_{B,0}})C_B}##...

The First law requirement would be as you have it Ches: ##\Delta U_a+\Delta U_b=-\Delta U_{spring}=-\frac{1}{2}k(\Delta V_b/A)^2## Where ##\Delta U_a=n_aC_{V_a}(T_f-T_{a0})## AM

I am confused by the P being the same on both sides. If it starts with the frictionless piston at rest and the spring stretched from its equilibrium position, the pressure on the right side must be greater than the left by ##\Delta P = kx/A## (where x is the displacement of the piston from its...

Does the 4 pole motor uses single phase power? I am not sure why you would have a 4 pole motor if you have 3 phase power. If it is a single phase motor, the pole windings will have to have different reactance in order to create a phase difference between the two pole pairs. So the windings...

Thanks for the link to the article. I live in Saskatchewan and I was puzzled by the article in our local paper today quoting Westinghouse CEO as saying that it does not require water (Saskatoon Star-Phoenix, Nov 27, 2023, p.1): I was interested to know two things: 1. how is it cooled? 2. how...

I would suggest that you be up front about it at the interview. Don't put it in your CV or initial application. It is not relevant until the interview. Don't mention it at the outset of the interview but don't leave it until the very end of the interview - the first and last things are what...

I was referring to the efficiency of a pneumatic motor to convert the energy in a compressed air source into useful mechanical work. Turbine fans working with compressed air can realize efficiencies of 65%. See: https://library.automationdirect.com/pneumatic-efficiency/ But you are right...

We agree that the use of compressed air proposed by the OP is a bad idea. Re: the point about the use of compressed air to run a pneumatic motor is not irrelevant. Pneumatic motors are actually quite efficient - not quite as efficient as electric motors but close - and much more efficient than...

Just connect a hose from the air tank to a pneumatic motor set up to run a compressor for the cooling system. It is adiabatic work because there is no heat flow - no source of heat involved. It would be more efficient to use the excess output from the solar array to charge a battery that would...

No. It would not be a heat engine at all. All work done by the expanding air would be adiabatic work.

I have looked at this again. If the idea is to use the excess output of a solar panel array to compress air adiabatically in a tank, let the tank cool down and then release the air to cool something, you are wasting most of the energy. First of all, the Joule-Thompson co-efficient (the rate of...

It is not clear what you are asking. If you are trying to use waste energy from a cooling system, you need to find some use for heat flow from the condenser. Modern supermarkets may have a central refrigeration system that will serve all the refrigerators and freezers. Instead of letting...

Feynman had an amusing take on the motion of planets: "...what makes planets go around the sun? At at the time of Kepler, some people answered this problem by saying that there were angels behind here [pointing to the side of the planet nearest the Sun] beating their wings and pushing the...

The first law was Galileo's anyway. Galileo did experiments with balls rolling down and then up inclined ramps separated by flat surfaces and noticed that the ball would roll down one and up to about the same height on the distant one regardless of how far apart they were. He concluded that...

All that matters are the initial and final equilibrium states of the gas inside the piston. To determine the final state you just need to know how much energy was extracted during the process and that just depends on the amount of work done. The difficulty in real life would be in determining...