Physics

If two sources, S1 and S2, of light are shining on a ball, and we are given the formula, L1(P) for the amount of light reflecting off the ball at point P caused by light source S1 and into a pixel, 'p' in the image plane of a camera, and similarly L2(P) is the amount of light reflecting off the ball at point P caused by light source S2 and into the same pixel, 'p', on the same image plane of the same camera. Then can we say the total amount of reflected light at point 'P' into pixel 'p' on the image plane is equal to L(P) = L1(P) + L2(P)? In other words, is there a superposition principle for the intensity of light? It seems that when two lights shine on a surface, th…

TSIA (The coordinates exists in reality.)

Is there any 'inert' liquid compound that generates electricity when hit by photons ? Like if sandwiched in conductive glass surfaces as electrodes. -I mean inert so will not erode electrodes chemically- Please move to 'Applied chemistry' if deserved.

Image Earth, our big ball. One flywheel is on the left (in a geostationary orbit), another flywheel on the right, perfectly symmetrical. The only thing that is asymmetrical is that the left flywheel is spinning fast and has two loads/parcels on 2 arms ready to let go of. At the right timing, they are let go of. I imagine they can be let go in a way that has them travel in orbit to the other awaiting flywheel in a orbit with the same height from Earth. Then they attach to the awaiting flywheel. This would lose minimal energy, while obtaining fast transportation possibly for advanced space construction for artificial intelligence. Is this possible, and if not, why? …

Enclose a positively charged sphere in neutral concentric spheres as shown in the image. Connect outer surface A to Earth, inner A to outer B, inner B to outer C and finally inner C to the central sphere. These spheres are good electric conductors and are insulated from one another. When you discharge a charged body using the laws of conservation of energy the electric energy of the current that flows is equal to the energy you put in charging the body, the description shows that on top of Earthing the system we can still get more electric energy flowing in different parts of the system due to the presence of the same charge. So little electric potential energy in the c…

I was wondering, If you're near to a blackhole... how far away minimum you have to be from it to be pulled towards it at a considerable strength, but not strongly enough to be stretched or ripped apart, in other words, alive and in one piece yet. How can I calculate that? Is there a formula, or a way to know it? Thanks; Arthur

Hi! My name is ufuk ı am 11 so ı am not someone knows how quantum physics work. Actually, ı am here to just find a physics game/simulator ı can mess with electricity and try to make a working engine etc.

Does the Earth have a natural frequency? Do the Laws of the Universe change with Time? How do the Laws of the Universe sustain themselves?

Planets orbit around a specific star, e.g. the sun in our solar system. What I observed is although billions of years had passed, still the planets orbit around the sun unchanged in it's position or even only a very tiny amount of change.. Why is this? Why planets are faithful to follow the course of their orbits? Can we infer that it's just the result of accident even it characterizes organization?

Obviously, a smart phone has very little gravity to it. And from what I've looked up, you could turn anything into a black hole if you get it dense enough. Let's assume my phone turned into a black hole, and I'm standing 5 feet away from it. The equation for gravity is F = G((m[1]m[2])/r^2) right??? So according to this, since the mass would be the exact same if it got super dense, my black hole phone, will have no more force exerted on me than just my phone... right? Am I being stupid? r is the distance between them right?

Hello everyone, Last day I had debate with my friend. She asked me this question: Does entropy increase with time ? Or Does it make Time? I have think on it but I couldn't answer it. Can anyone please help me to find this answer.

Hello everyone Let me address, after a long time, again the experts in the truly bizarre domain which goes by the name "physics": In my course, my professor says: [math]\alpha = 10\cdot \log{\frac{I_0}{I_x}}[/math] With [math]\alpha[/math] the attenuation of ultrasonic sound waves in a tissue, expressed in [math]\text{dB}\cdot\text{cm}^{-1}[/math], [math]I_0[/math] the intensity of the ultrasonic sound wave upon entrance of the tissue (or rather, right before it) and [math]I_x[/math] the remainder intensity after passage through the tissue of width [math]x[/math]. How is this even legal in physics? He basically states that [math]\text{dB}\cdot\text{cm}…

Are there any other things/objects in our universe that are massless other than Gluons and Photons? I guess energy is massless, but it's not so much a thing, more-so a property.

What have been the problems along the way and what are they currently working on?

In the link below: https://en.wikipedia.org/wiki/Orders_of_magnitude_(time) You can click on the word "Planck Time" in the top row, and it says that 1 Planck time is the the time it takes for a photon to travel 1 step forward. What I want to know though, is, is this a "made up" time like ex. there is a centrillion centrillion "mini" seconds per second, or is this really suggesting that a photon travels 100 tredicillion steps each second? Because I want to know how many real seconds or "moments" are in 1 second. 100 tredicillion?

Can anyone help me to solve this? A lifeguard who can swim at 1.2 m/s in still water wants to reach a dock positioned perpendicularly directly across a 550 m wide river. a) If the current in the river is 0.80 m/s, how long will it take the lifeguard to reach the dock? b) If instead she had decided to swim in such a way that will allow her to cross the river in a minimum amount of time, where would she land relative to the dock?

Anybody knows an interdisciplinary computer simulatior of science phenomenons ? that involve physics, biology and chemistry at same time, thanks!

I have read about plimsoll lines, while loading a ship, care is taken it should not be overloaded. Its load depends on density of the see in which it floats. the ship will shink if its load exceeds. Now my question is how to indicate depth up to which a ship can shink? And at what density value? which ensures stabilty and safety of the ship.

Help needed: I have a C-shaped permanent magnet as on the picture A). I sketched magnetic field lines between magnet poles... very close to the magnet, there is a current-carrying wire (perpendicular to your monitor plane). Some of the magnetic field can reach the wire and so I know the wire 'feels' a force F. In the picture B) there is the same setup, only now I plugged the gap with some magnetically permeable iron insert. My question is will the wire now feel a force F'? Is this force higher, smaller or equal to F? Can you explain what is happening?

Newton's law of universal gravitation states that F= g (m1 x m2)/r², i.e. a particle attracts every other particle in the universe with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. In Newton's view, there need to be two masses present for gravitation to take effect. It has been proven by general relativity that gravitation occurs with just one mass present, as it is not a force which acts upon objects per se, but rather on the space in between them. This all makes sense and Newton's law still holds true, as any two masses will behave in accordance to his equation. Howev…

What do you guys think about Lichtenberg figures ? In my opinion it is awesome. Im using a type of thin plywood known as 'underlayment' or 'backing board. Its basically a thin, 3-ply plywood with very thin wood veneers on either side. This works with any wood, but this type of wood gives the most consistent and best results.

which is which?

I was at the beach one afternoon in Australia Adelaide, I was young so I didin't think much of it but when I was running towards the shore (About average belly button deep) the sand under my feet was collapsing, I don't really remember it all that well but i'm pretty sure it lasted around 3-5 seconds, I was really scared so I attempted to sprint underwater. The only thing I could really think about (All I know about) is that it could have possibly been Angel Shark(s) but like I said it was in the afternoon so I doubt it. Thanks in advanced!

Einsteins relativistic train in tunnel paradox. There is a video on YouTube with this title. Towards the end of the video one person sees the length contracted train fall into the gap. The person on the train seems to see it become like a fluid that flows into the gap*. How can the train behave like this * i gather that this because the train is not completely rigid

|\/\/\/\/\/\/\/\/\/\/\|======================== ---> Took 356 Newtons to compress a spring 0.5 metre. A 1 Kg rod contacting its end gets pushed when the spring is released. Is that enough data to calculate the acceleration, or : Took 356 Newtons to compress a spring. A 1 Kg rod contacting its end gets pushed during 0.1 second when the spring is released to full extension. Is that enough data to calculate the acceleration ? What formula should be applied ? -Ignoring friction, drag- Is the calculated acceleration result the one at the end of spring extension; at position 0.5m away and 0.1 second from firing ? ( The initial force applied to the …