Physics

Hi I was reading about how putting nuclear waste into the sun would be pointless, due to orbital mechanics, and needing more energy than it take to leave the solar system, but what about black holes? does that mean it would actually be a lot more difficult to get into a black hole than people realise, my head says no but surely the same principle applys?, does it apply to spinning black holes only. Confused, please help.

OK. I really want to know something about equalizing pressures at deep ocean. Specifically what happens if you are in a hydrolock (as I'll nickname it, think of an airlock) and you fill the hydrolock with water and absolutely no airbubbles remain, then you open even a small valve to the outside pressure to "equalize the pressure". What I described is a torpedo tube. And it stands to reason that nothing happens. But my mind keeps going back to the engineering principle of waterhammer. If you have water at 1atm and you have water at 100atm and you bring them together, how do you NOT get a waterhammer? So in the torpedo tube example what is th…

I had an question about, how to understand more about wormholes and flying saucers. What do you need to study to get a grasp of something like this. Like math, physics, electric engineering, metalic engineering etc.. Thanks for reply.

Wasn't sure whether this was better for science education or here, but when in doubt, I go with "here." When I was a physics student, I always found it confusing that on ramps, the usual force components (cosine of angle off the ground for horizontal, sine of angle off the ground for vertical) were flipped for ramps. I get the reasoning for it, and I'm sure there are a bunch of mnemonics various teachers use for it, but I found that after I was no longer a physics student, and before I became a physics teacher, I spent so much time playing with programs like Paint Shop Pro that I found an even better way to remember it. First, you draw the ramp wit…

So I was recently thinking; hot air balloons, as a travel mechanism and leisure activity, use hot air for buoyancy on a large scale, and party balloons use helium on a small scale. Is there a way to form a middle ground between these traits? Not between helium and a large scale, but between hot air and a small scale. Is there any substance out of which a small-scale balloon can be made that can withstand steam (or at the very least warm, humid air) with which it is inflated and/or be well-insulated to retain its higher temperature for a non-trivial amount of its ascent through cold winter air? I ask this partly out of curiosity; partly …

I'm an outsider to the physical sciences. My only real skill sets to date are math (of the pure kind) and CS. But I seem to have an undying desire to pursue goals and ideas in the physical sciences. (I say "physical sciences" because I don't want to limit myself to physics, chemistry, or material science.) Many of my goals sit at the intersection of research and invention. Nobody is going to give me a lab and I don't have the means to build my own. Because I lack the means, I started gravitating towards existing hackerspaces (and possibly starting my own). COVID has put using hackerspaces to a halt. So, I started looking into using software simulations to experimenta…

Space - with its 3 dimensions (+ time) is distorted by mass --- no mention of changing dimensions. Possible extra dimentions (beyond the 3 +1) are considerred to only make sense if the dimensions are "wrapped up small" --- no mention of changing space. Why the different approach ?

It’s winter in the Midwest US. The air is extremely dry. This leads us to more easily build up static... picking up electrons. Our hair goes in funny directions. We shock each other when touching. It’s a fun part of winter. We also get shocked when touching the light switch on the wall since it’s connected to the ground of the house. The shock becomes visible at night, which adds a layer to the experience. Touching the light switch, feeling the jolt as the electrons flow from the finger to the lower resistance copper wire of the toggle switch into the ground, I can see the little micro lightening bolt jumping away from me toward the house ground. Bu…

Seems that if a laser beam is bigger than about 2 mm diametre it is not a laser any more ? Or is it still a laser even if the beam is 1 metre diametre ? How is that accomplished ? Diverging lens and collimator after ? The danger of vision impairment persists or is it greatly reduced as the light 'density' is a much smaller figure ? Which wavelength shows the beam brighter at night ? To achieve 1Km range on a 10cm fat beam at night, what power would be needed by educated guess ?

Does the cardboard material used in boxes protect from light and UV? I keep objects sensitive to light and UV inside these boxes example: DVD discs and plastics

I was inside a closed room and I used a hammer in wood and metal, the noise and sound and sound waves generated by the hammer beating may have damaged and cracked objects and DVD discs that are inside the same room?

So with the Celsius temperature system zero degrees is the temperature at which water freezes and one hundred degrees is the temperature at which water boils, quite simple. Fahrenheit is a bit more complicated with 32 being freezing temperature and 212 being boiling temperature. To the best of my knowledge Fahrenheit started out with 8 being the freezing point but then the entire scale was multiplied by 4 to give it a greater range and so 32 ended up being the freezing point, although I could be wrong. Zero degrees in the Fahrenheit system doesn't really mean anything unlike zero degrees Celsius which is when water freezes. The USA uses Fahrenheit although I believe…

Hello! I'm new here and I just wanted to try and show my theory to everyone so I could get some opinions and maybe some advice. Thank You 🙏 The Universe is 4 Dimensional, an entity existing in Space-Time flows through Time, then in Space. The delay existing in the movement of an electron for 1 second is 6.93907x10^-7 s . A body existing in 3d space is in a state of everywhere and nowhere meaning that it has no particular coordinates. When approaching great speeds, the delay in the movements gets bigger and more significant. The speed of Light is a limit for every body that has a noticeable mass. Information entering a 3d space only is lost. with Ekr: Relative K…

Does Energy depend on frames of reference?

So I was recently watching this video and I'm kind of left wondering why the cop doesn't just kick the leader of the pack down the stairs. The guy looks frail enough that the cop could've easily applied enough torque to make the guy lose his balance, which could serve both as a physical obstruction to continuing to climb that staircase and a deterrent against continuing to do so... especially if the falling leader of the pack ends up knocking over other rioters like dominoes.

I was looking into microwave gun and I found magnetron as a source of directed microwave. Now, is it possible to combine this with laser spectroscopy having magnetron being the power source(we all know how a radar works, it is just somewhere on the nanometer scale to visualize the brain) to visualize the brain? I have not worked out the power and wavelength required

Greetings. Often read "airplanes with 'high wings' are slower than airplanes with 'low wings' Why ?

So I was doing some last-minute Christmas shopping today and I noticed the fragile item they sold me was handed to me in bubble wrap. I presume that's at least partly because it's quicker, easier, and possibly cheaper than paying someone to attach a bunch of springs in all directions, but I also wonder if that's partly because the pressure would still be high enough at the exact points of contact with the spring as to still risk breaking the item. This got me thinking; it's one thing to protect property, but what about protecting people? Old-fashioned armor; be it scale, splint, plate, or chain mail; has metal in direct or semi-direct contact with the body it'…

Why is the shadow of an overhead street power line wider than the actual power line.

This reminds me of my original post.. What's the point of Calculus?? Maybe I should have asked this.. But anyway... Is Math and Physics "Interchangeable?"

So I keep hearing about how using a plugged-in appliance, or taking a shower, or using a water faucet, during a thunderstorm, can be a safety hazard because of the indirect contact with charge carrying conductors. However, this leaves behind the question; if the insulation provided by the exterior surface of your appliance, or the presumably salt-content-limited shower water, is inadequate to prevent electrocution, why is the air between an electrical outlet and furniture placed near it considered adequate? When arranging furniture, I never saw my parents pay that much attention to how close the furniture was to the electrical outlets. Does furniture provide a…

I remember reading somewhere about neutrons decaying after about 10-15 minutes of being free from any atomic interaction. This got me thinking that if you were to somehow reflect neutrons in a concentrated source then you would be able to form neutron fusion due to the neutrons decaying into protons. And because they are past the coulombic barrier they would be able to undergo fusion due to the weak force. This feels wrong however I am unsure why. Please correct me on where I am messing up. Thank you for your time and patience in answering my question.

It is how to understand dark matter when you reach light speed. ...warp speed is shown with no weight when you reach the speed limit

I have this old battery operated wall clock in my garage that has been sitting flat on a shelf for years not, not in use, with battery an AA battery that has not been replaced for years. I just went into my garage and I heard a ticking sound. To my amazement the clock had started to work. I took out the battery and put it back in but it didn't start again. The battery has one of those tester strips on the side. It shows it has 0 power. I tried the battery in another clock. Nothing. Perhaps someone had put a newish battery in the clock? but there were no finger prints on it (it's very dusty). So what on earth is going on? Do I have a ghost, or something more ratio…

Dear scienceforum.net, I once tried to include myself in a discussion topic that went under the label of "what is time?" in which many individuals entered with various perspectives either championing the non-existence of time with respect to change (including me) and others who took rather standard interpretations of relativity (special or general) to describe what they mean. I felt that given some of the resources or knowledge i've attained perhaps the discussion could actually go somewhere or be somewhat more productive. Over the course of those four years I had realized that philosophy had already been discussing this with already predefined terminology whi…