Physics

I have read that a single free neutron is unstable but then how a neutron star can exist ?

PLEASE, Help me out with this capacitance problem!!! I have been trying all my best to solve this question, most times, i end up in a dead lock and I leave it! I have just made a resolution to find the solution today. this is the original question; I redrew it and I had this; My problem is that there is a certain principle i think I should know in order to tackle that question, but i dont! any links to search?? We did the course last semester! how do I solve it? The question says I should find the effective capacitance. Thank You.

As the universe expandes is does not maintain a constant expansion speed, the expansion speed of the universe gets faster and faster. Spacetime itself is speeding up throughout the entire universe. Everything in the universe is speeding up. but we dont notice this so obviously, we can look at a clock and see that as usual time maintains a constant speed.... But Spacetime itself is widespread and affect all things in the universe. Is Spacetime Speeding up as the Universe Expands?

All Atomic Properties exist as waves.. But what is the First Wave that came into existence?

What is the meaning of earthing of any circuit ,I know its a child question . everybody says that it means 0 potential at that point but I didn't understand it till now I mean how current will be flowing after grounding in a circuit , what is the use of it in circuit other than 0 potential , how is circuit is completed after it ? Please help me

We all know that a proton binds to another proton through strong nuclear force but do also an electron binds to another , I haven't heard that there for asked ?

In special relativity, what is the equation for force?

Hello! How H-bonds effect on Raman spectra? Can we determine are there H-bonds in molecule with Raman spectra?

I have read that an electron and positron create two gamma photons after collision but is reverse also possible ?

The theory of everything is the most interesting research topic extending to almost all academic disciplines (arts or sciences), and to some; it is called the holy grail of science. Most interesting to me because when it is dicovered,it is expected to reconcile between logic, reason and natural phenomena which will provide a correct yardstick for future research and phenomena implementation. In philosophy(which is the grand parent of all sciences), even if you have all other answer to everything with out answering why- you can better go and dig your own grave. With phenomenology, reason without logic is daft. That is why Descartes found tough times w…

Everything that anyone knows about dark matter is just that it is there and it dose not react with anything it touches, goes near, or anything. But dark matter is present which is how galaxies are given the weight needed to rotate around each other and not fly apart. But, there is one thing that many people do neglect to look at even though it is right in front of their faces. Does anyone remember that trick where you leave a beer in the freezer for about 15 minuets and take it out, it is not frozen but if you knock it slightly on the bottom of the bottle the molecules will start to freeze from the bottom of the bottle up. Dark mater is present even though …

Why do two photons never collide I mean when two light rays intersect each other they do not form any resultant just passes each by ? Why and how ?

Is there some lower (or upper) limit to the wavelength of a photon. Like macrowaves or something?

For the purposes of a sci-fi story, what would be the effects of a large nearby electromagnetic pulse on a car, and what would it take to get it running properly again? Thanks in advance for any help

Hello, I saw this movie on youtube : "Free energy generator - Make ice cube with microwave oven " This film shows how it is possible, under certain conditions, to make a microwave oven work in a particular way to generate cold ! Is it really possible to make ice cube with microwave oven ? Thank you.

Hello everyone I'm making myself a new problem concerning kinematics, trajectory, ... And I'd like to know something: if a car with FWD jumps over a ramp: 1) Is it already following a parabolic 'trajectory' when the front wheels leave the ramp? Or only when the back wheels also don't touch the ramp anymore? 2) Can the car (theoretically) land on the ramp on the other side in that way, that the back wheels just make it on the second ramp? I know this might sound a bit awkward, but here's the problem: assume that the car will hit the second ramp with his front wheels at a point (x,y) as defined in y = y0 + xtan(theta) - gx²/(2v²cos²(theta), will it land in the …

Hello, Background: I was going to implement an implicit approach to 3d tetrahedra deformations (first in Matlab then in C++). I need the Jacobian for the partial derivative of force wrt position to do this. I found this paper that gives a method for computing it: http://www-bcf.usc.edu/~jbarbic/Barb...nessMatrix.pdf The Question: In the report, he defines a 2skew function (to the right of the page). I'm pretty confused on what it means. I think I forgot what skew means from linear algebra - that's probably part of my problem. It sounds like skew symmetric means that a negated matrix is equal to its transpose. What exactly is this 2skew function for?

Why do an electron never stick to its nucleus I mean both opposite charges attract each other but why they never stick to each other (like in Bohr's model) ?

Instead of using gasoline to fuel engines, what if acetylene were used as an alternative to gasoline. It has more energy per mole, and would only require compression to combust eliminating spark plugs. If not put to commercial use, could it still be made? ~EE

I have a couple of questions, Moderators: If it's in the wrong category, go ahead and change it, please don't ban me. If you set the background of a computer screen black, would it lose less energy than if it were white? If you were to place a cover over the screen so that light cannot escape, it would transfer to heat energy correct? Please could somebody explain to me the process of the transformation of light energy to heat energy? Thanks,

Reason: I have this digital camera " sony" high quality good mega pixels that does not give great " clarity photos" when the photos are taken in doors, " regardless of the settings" IE, outside mode, indoor mode etc.. However: When photos are taken outside or at the beach for example, the photos are crystal clear! Again: " regardless of the settings" I wonder if it is the flash that is low quality, but then again: Isn't anything that creates ie " light flashes, light bulbs not including lasers, all " forms or light photons"?

Hello everyone I have a question about something I really can't stand in physics: approximates (the rules which say that if you have a sum or a difference, the result may not be more accurate than the less accurate term; if you have a product or a quotient (ratio?), the number of significant figures may not be higher than the number of significant figures of the factor with the less significant figures) (I can't stand these approximates for their inaccuracy ) To exercise this, I've used a self-made example: A bullet is being shot at a height of [math]276.457 m[/math], under an angle [math]\theta[/math] of [math]0.524 rad[/math] and with an initial veloci…

I actually am not quite sure whether what I am referring to would even technically be referred to as 'holograms' per se. Basically, does anyone know whether or not the fully three-dimensional (as opposed to merely virtual three-dimensional) projecting technology seen in science fiction movies like Prometheus are possible even in principle? I'm referring to the common Sci-fi thing where a 3D image is projected seemingly into empty space/mid-air and a person can literally walk right through it without disturbing it in the least? Would that be holography or is that something else entirely?

what makes an object transparent and opaque like in case of carbon , graphite is a black opaque substance but when heated to a high temp. it converts to diamond which is transparent in spite of it is denser than graphite ?

Do all the Gauge Bosons move at the speed of light, or only the photon?