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If you have a pyramid made of spheres, like cannonballs: the First Law says that the total number of cannonballs will never change. The Second Law says that over time the pyramid structure will fall a …

I think "heat rays" is a very loose and informal term, so don't take it too strictly. The usage probably stems from the fact that most objects are at a temperature that primarily emits IR. To start e …

The partial and total derivatives are different things, but they are related via the Chain Rule: For $f(x,y,z)$, the differential of $f$ is: $$df = \frac{\partial f}{\partial x}dx+\frac{\partial f}{\p …

It would be far more efficient and feasible, if you had access to a black hole, to convert infalling matter into radiant energy via the accretion disk and/or a Penrose Process. For the best case of a …

Powder filled vacuum (I don't know if sand per se is used for this purpose) is in fact used in cryogenic insulation, and can be better than vacuum alone, because vacuum alone is susceptible to radiant …

Remember that when we talk about the big bang, all we can actually do is take the current universe and extrapolate the clock backwards in time. We do this using General Relativity ($\Lambda \mathrm{CD …

I think you understanding of how the hot water heater (not a boiler, incidentally) system works is way off, if you don't mind my saying. The temperature setting means that the heater will kick on unti …

Newton's 3rd law only describes what I consider to be the same force that acts on two objects, not two different forces. And forces not acting on the same object can never sum or cancel each other. Th …

I believe you are confusing "force of gravity" with "pressure." The gravitational pull (or local acceleration $g$) is indeed zero at the center of the Sun, and a maximum elsewhere in the Sun (whereve …

The example you described is not really an illustration of the 2nd Law. Picture rather a helium balloon in a room. Equal pressure inside the balloon and outside. Then the balloon pops. Although at fir …

I have actually done this very experiment, starting with a sealed, permeable vessel (Teflon) filled with helium at 1 atm surrounded by air at 1 atm. What happens is over several days the pressure fal …

B) If you're referring to the 1st Law of Thermodynamics (Conservation of Energy), the universe as a whole does not obey conservation of energy. … The science of Thermodynamics takes CoE as a postulate that is assumed, and makes no attempt to derive it that I'm aware of. …

In some thermodynamic contexts, the inverse temperature $\beta=1/T$ is a more meaningful quantity. This makes it more clear that 0 Kelvin, or $\beta = \infty$ is approachable but unattainable. And …

The tire rolling will never make it colder than it was sitting idle. The air is typically colder than the ground surface, so the tire surfaces touching air will be at least as cold if not colder befo …

Your first sentence is incorrect. If A and B are timelike separated, their order cannot change, even if the time interval and space interval between them change with the observer. If they are spacelik …