Physics

Hi, Do EMP devices exist that can disable/power off all electronic devices within a given radius? Eg. Such as the one contrived in Prison Break season 3 episode 5. I was once told by a Russian friend of mine that when he was in school, his friend had made such a device to power off people's mobile phones with a range of about 5m. How do they work? Are they used in police/military operations? Thanks, pyroglycerine

Why is energy equal to mass times the speed of light squared? It doesn't make sense to me. Why squared? Why the speed of light?

It is stated that the speed of light has no mass and does not exist in this dimension. IE Statically known to exist in the known regions of time but not space.. Also the consideration of particle waves adds more speculation to the OP's question. If a person were standing in-front of a mirror and light rays were present, how can " information" from the light beams travel into the retina to the brain and project a virtual image for the observer upside down??--> again photons carry no information, are mass-less and do not exist in this dimension... This would also mean that depending on the person seeing themselves in the mirror that "distance" is an issue, I…

As a cosmic observation the unique characteristics of galaxies appear to have a correlation to the kinetic energy exhibited by the central black hole. The direction of rotation of the black hole appears to be ascertainable by the shape of the galaxy, particularly the position of the outer arms of stars. Also, the planar nature of galaxies appears to result from the rotational velocity intrinsic to the black hole. - Side question, is it likely that there were bodies outside of the galactic plane affected by the rotational velocity of the black hole that would have collapsed into the black hole thereby increasing it's mass initially? Does the rotation of a black…

have: proton mass 1.67*10-27 kg and speed 10 000 km/c = de Broglie wave - A electron mass 9.1*10-31 kg and speed 10 000 km/c= de Broglie wave - B and atom of hydrogen consisting of proton and electron. mass atom of hydrogen 1.67*10-27 kg + 9.1*10-31 kg , speed 10 000 km/c question what will be de Broglie wave atom of hydrogen? alleged options: 1: the electron of the hydrogen atom = de Broglie wave - A the proton of the hydrogen atom = de Broglie wave - B this seems logical 2: de Broglie wave atom of hydrogen= С ( С<B and C<<A ) this option seems not logical,because the electron in the atom has a mass of free electron and the el…

Hello to you all, my name is Leonardo and i'm 17, i was studying for the tomorrow's phisic test when i wondered what would happen if antimatter and matter "walk up".. Would there be gravity or it could be called antygravity? I thought that if the eletric force has a positive part and a negative part, maybe matter and antimatter could act as the same! Do you know something about it? Now i feel a little stupid, i'm just a guy who can't neither speak well english.. Ahah ok that's all, bye!

Would any one please explain me the working and use of capacitor (commonly called condenser) in a fan . Please don't tell the working and use of a simple capacitor.

Alright guys if the locomotives have their front surface completely straight then the force acting over it is maximum in some cases might not cause locomotion move but if it has an angle of 45' the force reduces to half but if it reduces to 30' or something less still it remains same . So does it mean that the force acts maxima 45' only.

Let's assume a machine with substance A as the fuel. The output of the machine is electricity plus a product B. 1 kg of product A yields 1 kg of product B and C kWh of electricity. If the calorific value of product A is for example 20 MJ/kg and of product B it is 15 MJ/kg The electric output C of the machine from 1 kg of fuel A is 2,777 KWh. 1 kg A ---> 1 kg B + 2,777 kWh electricity A simple attempt to do an energy balance based on the calorific values gives the following: 20 MJ ----> 15 MJ + 2,7777 kWh 20 MJ ----> 15 MJ + 10 MJ Is this a possible situation? If so, how can it be accounted for that the energy content of the reaction produ…

If a black hole is of infinite density but Zero diameter does that make it a 2 dimensional or a 1 dimensional Object

Hi folks, Info on microwave ovens often talks about the direct efficiency of converting electrical power to microwaves. Ok, that's pretty straightforward; I am NOT asking about that. I can't find much of anything that addresses the "efficiency" of the microwaves that are created, being converted to heat in food. Said another way, what happens to microwaves that "miss" the food; are they simply lost? Many illustrations showing magnetron emissions appearing to bounce around in the oven, and info says the walls are highly reflective... do they keep bouncing until they hit food, conferring very high efficiency? Or is this even the proper way to think about it, sin…

Could someone please give me a complete list of all the mathematics that I need to know in order to be able to understand quantum field theory and string theor/superstring theory/M-theory.

Just having some difficulty visualising how electromagnetic waves transmit energy. It is easy enough to visualise when waves propagate in a medium -the kinetic energy of sound waves for instance. But light does not need a medium to propagate. Is the wave itself energy, though i'm not even sure what that means? Is it the disturbance in the electromagnetic field which carries the energy? This i can visualise but then i'm missing something else as it would then seem that light is propagating through the electromagnetic field - contrary to what i have learnt.

Honestly, I am amazed to those who can express formulated theories in an understandable language of those who don't have such knowledge in the field of physics. But, I want to know the opposite. How does a person who just got an idea about something to formulate it in the language of mathematics and physics?

After watching a show on Multiverse and Multi dimensions, they outlined there could be Possibly 4 different types of Multiverse's, saying that one of them,dictates our Universe to be Infinite, yet there also be an number of Infinite Multiverse's contain exact copies of me and everyone on the earth, Varying slightly or Drastically in Difference and Lifestyle, i think to my self if our universe is infinite why would there need to be copies of a thing that is infinite to begin with, and as to the copies of Us, why would there be a universal or multiverse law to be exact an have the same of everything just differing is some way..?

Hello everyone Let me just ask it: If you look to the image below, which mass would need to be on the question mark? (I never treated this kind of matter at school, yet I fear this is a very good question for the Med School Approval Exam) I'd say: [math]2(M\cdot g)=2(2m\cdot g)+6(5m\cdot g)=34 m\cdot g[/math] [math]\Leftrightarrow (M\cdot g)=17m\cdot g[/math] [math]M=17m[/math] Yet I fear this is wrong. Don't know why. Thanks. Function

I'm reading and learning about the Higgs boson at the moment. So, I'm just throwing out a question: Does the Higgs field cause light to have its constant ("speed of light")? I'm speculating from what I've heard and read of the Higgs boson. It seems like the bosons are the sands of time. However, I'm more focusing this thread on the speed of light. Because if what I heard is true, then the Higgs field does not affect the speed of light. However, I consider there may be more at play in that the Higgs field gives light its speed, thus the Higgs field acts as a constraint on the speed of light. Thus, I question if there was a way that the Higgs field could be repelled or …

Hi, I'm working on this science experiment in school, I don't really wish to go into details, but I would like to use this experiment I found online in this article: http://phys.org/news/2011-07-coke-cans-focus-diffraction-limit.html I have tried to mimic as much as I can from what I found out on the small article but I'm having trouble recording the resonating tone of a can. So far I have used a simple phone microphone but it captures the overlaying tone and the resonating tone is faded in the background. I'm wondering if anyone would have any ideas of how to get a finer recording of the resonating tone. Unfortunately, the article I discovered the experiment …

Can lightning produce gamma rays?

So in 2019 or 2020 the ITER (Pronounced "eater") will be finished hopefully. I myself am skeptical as to it being finished by then. I'm 14 so if the plans go as according it'll be great because I'll be able to see the beautiful price of scientific ingenuity and machinery in action. I would kill to work at this thing. But like I said I'm skeptic about it. And not to mention what the scientists working on it are saying. That this beauty will pump out 10 times more energy put into it. That means there's a viable option of pursuing a bunch of reactors if it works as planned. If this happens it'll be the day I cry out of pure beauty. Now my field of interest is nuclear fusion …

A friend I know has recently got an interest into the theoretical of Black holes and I wanted to recommend some literature on Black Holes. Since I mainly work in the field of mathematics and computer science, I wanted someone else's recommendations. So, can anyone give a list of recommendations of literature for new physicists about Black Holes?

Proof of the existence of God found in Colombia? An image found on a rock in Colombia violates laws of Physics and all that is known by science... the image is part of the rock and the colors are part of the rock itself. so the image was formed with the rock... Explanation?... Anyone?...anyone? http://third-secret.pro-forum.co.uk/h65-final-proof-of-the-existance-of-god-published-in-colombia

Hi, Fundamental frequency is the lowest partial in signal analysis, and the harmonics of the fundamental are multiple integrals of that. But I've heard of 'subharmonics' where people are claiming that you can have integral fractions of the fundamental frequency in music. don't understand this, as I thought the fundamental was the lowest, by definition. Anyone who is clued up in Acoustics that could perhaps explain this in more depth? Is there such a thing as subharmonics and how does work in relation to the fundamental?

on these forums. Books that have been recently denounced: ISBN 0-316-15579-9 The Cosmic Landscape ©2006 Leonard Susskind First Edition: December 2005 Little, Brown, and Co. New York USA May I please have an explanation why this book is not acceptable as a reference on this forum, since it is a legitimate publication by a famous physicist? Thanks in advance. Please be aware I will be informing Dr. Susskind of your response. You should be aware that he has responded vigorously in the past to accusations against him similar to yours. Good luck. While we wait, I will append a list of books you appear uncertain about: Albert Einstein, Relativity…

How Much Uranium need for run a 100MW nuclear power Plant (working 24 Hrs day )for a year swansont-total uranium in Kgs