Recent content by Rensslin

Got it: that makes sense. Thanks

@phyzguy I was told that there are communication satellites that are constantly stationary. That is how they can communicate with the ground; if they move around the planet then they quickly lose communication with their station. Is that wrong? If a stationary satellite “falls“ it must start...

@boneh3ad. Well I think entering Earth's atmosphere could be kind of like a bellyflop. Here you are cruising through space with no aerodynamic drag; then all of a sudden, you have a condition that dramatically restricts your speed. Failure to consider angle could have injurious results.

Thank you for your careful consideration; thank you also for your thoughtful responses. And thank you for directing me towards the forum rules. I will carefully consider them. I don’t believe I’m being rigid. I suppose no pigheaded person does. I once argued with my high school Physics...

I hope I’m not being disrespectful. It would be easy for someone to see a gas being compressed, note that the temperature at the point of compression increased, and wrongly think that heat was “produced”. Consider this: when you spray dust off your keyboard from a can of compressed air, The...

First of all I’d like to thank everyone for helping me with these concepts. Second of all I’m doubling down on my statement that and object hitting the earth’s atmosphere is like a bellyflop. Second I may be wrong about not believing that kinetic energy might be somehow changed into heat...

First of all thank you for validating my initial concepts. Re-entering atmosphere is like a bellyflop off of the diving board. You are moving through a gas is one condition at a speed that the water will not accommodate. I am flattered and honored to dialogue with a mind like yours; I...

It helps a great deal. I had a lot of trouble getting my mind around gas compression producing heat; my physics teachers were just poor explainers for my little one-cylinder brain. I couldn’t figure out how my foot-powder can got cold when I sprayed it. I don’t believe the compression of...

I can’t get my mind around how things “burn-up” upon entering the atmosphere. I envision some kind of bellyflop. Objects have no friction prior to entry. But how is this different from an acceleration within the atmosphere? Is the speed of the object faster than can be attained within the...

So I have a slab made out of super concrete. I drilled holes for something that will expand and pop the slab. But the product for sale is outside my budget for 50 x as much as I need. Does anyone know a compound that will slowly react to expand forcefully enough to break up the slab?

So if I drop an unopened can of beer and it doesn't explode, I notice the pressure on the can has increased. Avdgrado...(the French guy) states that the contents have not changed. While I put energy into the beer via dropping it therefore energy is not matter; or at least it does not exist...

So if you took a liter of cold air and counted all the molecules, it would have more than what you would have in a liter of warm air. If you then compressed each of them into 500 ml you would double the atmospheric pressure. Right? If you compressed them again into 250 ml, you would double...

Aren't pressure and density synonymous? At least when it comes to air?

I think cold air is more dense than warm air because if I put an empty water bottle in the freezer over night it will crush in on itself. But I don't know if this principal is universal for cold or hot air. I think your question is a good one. I think I can make a way to get a thermometer...

So, in this case cold air is not more dense than warm air, and therefore, cold air is not necessarily more dense than warm air, but only in some situations.