All Questions

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Reg position of satellite

Is it possible to put an artificial satellite into an orbit in such a way that it will always remain direct over a city (I mean at any specific place)?
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What is the largest number of bosons placed in a BEC?

What is the record for the largest number of bosons placed in a Bose-Einstein condensate? What are the prospects for how high this might get in the future? EDIT: These guys reported 20 million ...
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Error in standardized mass-energy of deuteron?

There is a problem with data that I've obtained over the internet. Here are the two sources of information from which I'm retrieving my data. NNLC and NIST On NIST, I have read that the mass excess ...
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Good introduction to classical mechanics with math [duplicate]

Right now, I'm reading "Classical Mechanics" by Kibble and Berkshire. Already in chapter 2, I have found a concept being discussed that assumes you have prior knowledge. Specifically, it describes the ...
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Why are unilateral Laplace transforms suitable for causal systems and bilateral aren't?

https://en.wikipedia.org/wiki/Two-sided_Laplace_transform#Causality The above section says that bilateral transforms will not necessarily make sense for causal systems. In the course of advanced ...
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A model that unifies the strong, EM, weak and gravity forces?

Does there exist such a model that explains the force clusters (their origin, relations between them): the strong, EM, weak and gravity forces?
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Is it possible to express various nonlinear motions as straight lines in transformed spacetime?

I am trying to understand simple examples of space-time curvature. Assume for the moment that $c$ is infinite (classical curvature due to Newton's laws). Also, I will only consider 1+1-dimensional ...
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vision problems [on hold]

While picking up a pair of eye glasses dropped by a friend, you notice that they form an inverted image of the background and that the image is stretched horizontally as well. Your friend suffers form ...
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Condition for formation of interference pattern

I recently came across this in a textbook of mine while studying the Young's double slit experiment. It says a condition for the formation of interference pattern is s/S < lambda/d Where s is ...
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Current lagging voltage by more then 90 degrees

According to Wikipedia https://en.wikipedia.org/wiki/Leading_and_lagging_current An alternating current that reaches its maximum up to 90° behind the voltage producing it is said to be lagging. and ...
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Comparing voltages of Parallel and Series circuits

There are two electric circuits. Resistor 1 ($R_1$) connected with resistor 2 ($R_2$) by series circuit $R_1$ connected with $R_2$ in parallel Each of the circuit has battery with emf and the ...
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How do two electrical charged particles know to repel or attract each other?

Now per QED, electrical charges interactions are effected by photons. Suppose you are one of the two charges. How do you know to attract or repel the other charge? In other words, how do you know if ...
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Viscosity and surface tension

Both viscosity and surface tension are dependent on the intermolecular forces between the molecules of the liquid. Supposing from this, shouldn't there be a directly proportional relationship between ...
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Does dispersion take place in our eyes? [duplicate]

What do we see if a single ray of white light falls in to our eyes ? Doesn't it undergo dispersion ?
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Temperature to make oceans evaporate [on hold]

The Boiling point of the water is 100 C after that water evaporates. If we are to heat the water of all the oceans combined, what should the temperature be set at, so that all the water gets ...
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How does low entropy in the distant past translate into the observed entropy increases?

One of the explanations of the second law of thermodynamics is that it goes back to the low entropy in the early universe (How do you prove the second law of thermodynamics from statistical ...
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Why scalar function of vector can only depend on norm of vector?

In Field Quantization by Greiner and Reinhardt as well as The Qunatum Theory of Fields by Weinberg, concerning the spectral function, the authors say a scalar function of the four-vector $p^\mu$ can ...
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Why is the fact that our universe is fine-tuned to life [on hold]

Why is the fact that our universe is fine-tuned to life not convince most people enough that the multiverse is real. we have to choose to believe now since it can't be proved directly forever. I don't ...
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Irreversibility of the nuclear decay process: is there a rigorous proof?

Consider an unstable nucleus that emits an alpha particle. For describing the process we solve the Schrodinger equation using a complex energy, and obtain a Gamow state. The mere fact that we use a ...
326 views

Why do the high frequency waves have the most number of modes?

While reading the Wikipedia page of Ultraviolet Catastrophe, I came across how Rayleigh and Jeans applied the equipartition theorem. They told that each mode must have same energy. Now as the number ...
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to find work from that question kindle give some idea [on hold]

A set of friction less wheels are attached to the bottom of a box, which is then measured and found to have a mass of 6.0 kg. The box is placed on the floor, and a student of Physics uses a brief ...
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Why is microwave better than visible light for point to point data communication?

In the electromagnetic spectrum, it appears that the shorter the wave length, the better the bandwidth due to higher frequency. Some communication systems utilize microwave to transmit data to offer ...