I am a student of physics at graduation level.I want to Masters and PHD in CSE in USA.  can it possible?
When applying to a PhD program in the US, how does the admissions process work? If an applicant is weak in a particular area, is it possible to offset that by being strong in a different area?  Note that this question originated from this . Please feel free to edit the question to improve it.
I read in  in this site that the KE a free-falling ball acquires is not originated by the attracting body but that energy was actually stored in the ball when it had been lifted to the height it dropped from.  In this way, it was said, gravity is subject to the conservation of energy principle and cannot change the total energy of an object.  Consider now the maneuver known as a  (also gravity assist) used by space probes such as the . A space probe approaches a planet with velocity $v$, slingshots around, and ends up with velocity $v+2U$, where $U$ is the velocity of the planet.  Consider the energy of the probe. Before, it was $E_i=\frac{1}{2} mv^2$ and after it is $E_f=\frac{1}{2} m(v+2U)^2$. It looks like $E_f$ is much bigger than $E_i$ - but where did the additional energy come from?   Is this not a violation of the conservation of energy principle? IANAL et al. is usually the start of answers to [legal] questions on any SE site (e.g. ). You usually end up with personal opinions which sound sensible and the accepted answer is often the one closest to the OP's hopes. But it's probably often not correct. I know the situation can be rather complicated and even differ by location, but it would be really helpful if the SE team were providing official lawyers (indicated maybe by using a § in the username, forbidden for everyone else, just like the mod ♦) to provide some orientation that one could actually rely on beyond much doubt... "Email" or "e-mail"? Which way of writing the word: "Email" or "e-mail" is correct? Both variants seem to be in wide use. If both ones are okay, maybe there is a difference in contexts they have been used (one is more formal than the other)? How do I access a specific element in a vector of vectors clojure Say I have two Chrome windows open like this:   It seems that the most recently used window always appears on top. In other words, the &quot;Apply Digital Signatures&quot; was the window I had open last. If I were to switch to the window showing the new tab, then the order in which the windows are displayed in the task bar suddenly changes. Is there a way to keep them from shuffling around? I'd like to be able to order them however I want, like tabs in a web browser. (I'd also like to put them across different workspaces.) Example of a finite non-commutative ring without a unity Give an example of a finite, non-commutative ring, which does not have a unity.    I can't think of any thing which fits this question. I was thinking $M_2(\mathbb{R})$ but it has the identity. Any help is appreciated. What happened to Saruman after he was knifed by Grima? How to typeset asymmetrical confidence level limits / uncertainties? Below is an example of an asymmetrical limit (or uncertainty)  How can I typeset this in a \LaTeX equation? Such pair of numbers should be vertically stacked while being vertically center-aligned with rest of the equation. Solution $X^{+Y}_{-Z}$ How many digits does $2^{1000}$ contain? I tried this way, I only need to know if this is correct or if there are better ways to solve this:  $2^{1000}$ does not have a factor of $5$ obviously therefore we can assume  $$ 10^{m} &lt; 2^{1000} &lt; 10^{m+1}$$ for some  $m$   Assume $ k = 2^{1000}$, then take log on both sides $\log k = 1000  \log 2 \approx 301.02999 &gt; 301$  Therefore $2^{1000}$ has $302$ digits. Data defined label position for more than one scale in one layer I'm looking for a better labeling-solution for my projects. It seems to be difficult - but maybe I'm just blind?   My projects: I build  printed bike-hike-books. The main scale is 1:75k and there are a city scale of 10k and a overview scale of 200k. Because I like to have a "cartographic" quality of labels placements, I touch every single label and move it to it's best position. I have to do this for every single scale so my labeling columns for 3 scales look like this ('scale 1' stands for 10k 'scale 2' for 75k  and 'scale 3' for 200k):    But before I try to explain in detail, I build this simple Example-Project where you can see and test my (old) labeling solution for 3 scales:   Well, it is working but:    You need labeling columns for every scale  You need a layer for every scale   I'm looking for a much better solution without duplicate layers and tons of columns. I count on your creative minds!  EDIT: I added this two very dense map as examples:    There is only one single possible position for "St. Paulus Dom" and it's not any quadrant:   Every label has to be moved manually. Some of the labels are not in a quadrant. I am new to blender (yes, laugh at the obligatory doughnut) and I when I set up the camera (I use NUM 0 to access the camera and move it into position with &quot;Lock camera to view&quot;) in the viewport it shows as the first attached image, but when I render it the image is further back as shown in the second image. Is this normal behavior or am I missing something? Can the program counter on Intel CPUs can be read directly (that is without 'tricks') in kernel mode or some other mode? Lunch Meeting Probability for two person to meet in given 1 hour slot and none would wait more then 15 minute. Two friends who have unpredictable lunch hours agree to meet for lunch at their favorite restaurant whenever possible. Neither wishes to eat alone and each dislikes waiting for the other, so they agree that each will arrive at a random time between noon and 1 pm, and each will wait for the other for 15 minutes or until 1:00. What is the probability that the friends will meet for lunch on a given day? How can wifi penetrate through walls when visible light can't? I did search the question on Physics S.E considering it would be previously asked. I found this  But in this question , the answers are w.r.t to or in comparison with microwaves , their absorption and certain other things. I didn't find a sort of general answer that could be the answer to the question. So the question is - wifi or radio waves  reach us through concrete walls . They also reach us through the ceiling (if some one is using it in the flat above ours ). Even through the air they travel such a lot , bending around corners or doors . Now I would not compare them to microwaves (because I don't want the answer in terms of properties of the material but physics). Visible light which is so much powerful than them can't penetrate black opaque paper leave alone the walls. Same is true for gamma rays (penetration through a very thick wall). So why then radio waves being so very less powerful than light  waves are able to travel through walls? There should be a general concept as to why the radio waves are able to pass through walls but microwaves or light waves cannot ! A linked question is also that sound travels much faster in solids(walls) but is not audible in it though it is in air. After reading @BillN's answer, it would be really helpful if any one could explain it in terms molecular resonance or crystalline structure or electrical conductivity or how does molecular resonance or crystalline structure or electrical conductivity cause this. Show that there are $ a,b \geq 0 $ so that $ |f(x)| \leq ax+b, \forall x \geq 0.$ Desoldering/soldering 1/4" chip with eight pins Placing math environments inside math environments I have a macro which appears throughout my document in various places:  \newcommand{\placefraction}[2]{     $\frac{#1}{#2}$ }   Sometimes it is placed with regular text. Sometimes it is placed within other math modes. However, the document won't compile if it is placed inside another math mode.  None of my math ever appears in displayed formulas, it is always part of the paragraph.   How can I have a macro which sometimes appears inside math mode, sometimes outside, but itself contains math mode? Creating point to center of polyline? I'm trying to create a points in the middle of polylines. The data is now in the form of shapefile. Is there an easy way to do this? How to create a timeline with LaTeX? Trying to Get the Most Cooling Power out of TEC Peltier Element: Smaller or Larger Peltier? I am trying to achieve the strongest cooling effect using a TEC Peltier element.    Currently, my set up is two small, 20mm x 20mm peltier TES1-4902 run with a 5V 2.4A USB Battery Pack per peltier.   I need a way to reduce my costs while keeping the same cooling power.   Right now, it is expensive for me to run this set up due to the fact I need two batteries, and I am also looking to improve my efficiency while cutting out an entire battery and/or Peltier. The reason I have two separate battery packs is that I can not find a cheap, small, and thin battery pack that will output 4.8 Amps: however, putting two battery packs in a series may help eliminate one peltier.     So, I have a few branching question that center around a theme:  1) Would a larger Peltier allow for a stronger cooling effect as a result of a larger surface area, say like a 50MM x 50MM peltier, despite the fact (presumably) that it may be more difficult to cool one single peltier than 2 smaller, seperate ones?   2) Is there a Peltier size that would allow me to reduce my power consumption while maintaining a similar cooling effect?   3) Is there a way that I can output 5V 4.8A that is not in two separate USB battery packs that is small and relatively cheap, as battery price:output ability for small scale consumer is quite high and USB battery packs have been the cheapest source of sustainable power for me.    My problem stems from the fact that I am trying to pump as much power and achieve as much cooling power as possible without having to have, say, two battery packs and make the project too expensive. I need a way to reduce my costs while keeping the same cooling power.