Forget about what causes what. To calculate work done by a particular force on a given object, you only need to know what that force is and what the displacement of the object is. It doesn't matter whether "only part of the displacement was caused by the force" or anything of that sort. You look...
I was reading the Feynman lectures and in one of the chapters on thermodynamics it is stated that stretching a rubber band makes its temperature rise. I feel like I understand the thermodynamics of the rubber band and yet this statement is puzzling me. I believe that when you stretch a rubber...
How much does your GPA during grad school matter? I understand that research is the main thing here but still I wonder. I just recently ended a semester with a B and a B+ and I am not very happy about it. I feel like I worked a lot for both classes and I expected higher grades. I am also pissed...
Thanks for your reply jtbell. I am still confused as to why then does the aperture have to be comparable in size to the wavelength of the wave. If diffraction always occurs anyway, then why is it that light is supposedly not diffracted through a door opening?
Hello, I have the following question:
Physics books say that in order to see diffraction you need a wave to encounter an object that is comparable in size to the wavelength. This is presumably the reason why light does not bend through an opened door but sound does. My question is, what...
Bill_K thank you so much! That was the kind of answer I was looking for.
tom.stoer your answer was helpful too.
Simon, I think you misunderstood me, but I was not trying to change the definitions of the physics language, but merely trying to understand what I was missing. I think you should...
This is a question I've had for some time now.
Why is the exchange interaction not considered a force, like the other 4 fundamental forces? When reading solid-state physics texts, for example, I come across explanations of this kind: the atoms cannot get too close together because of the...
I've read several not-very-scientific articles about graphene. What puzzles me is this: It is supposed to be a one-atom-thick layer of carbon atoms, and it is claimed that it could work as a display (like a very flexible screen or something like that). First of all, how would we be able to see...
Well a very simple way to do it would be to first "shrink" your range from being -β to β, and making it 1. You can do this by dividing by 2β, and you get p'(x) = 0.5 cos(\pix)
Now your function covers -0.5 to 0.5 so what you have to do now is move its range "up" by 0.5... so you get p''(x) =...
I was well aware about getting responses like your first point. The thing is: if you absolutely love 2 fields in physics, and you could put your heart into both, but you knew you could land an academic job in one but not in the other (or at least less probably), which one would you choose? Of...
I know job prospects in academia suck, but what, to the best of your knowledge, is the field in physics with the most promising future as far as jobs is concerned?
By getting a Ph.D. in what field do you stand a better chance of getting a postdoc position?
Just a couple of thoughts:
Do what you love, not what will give you money.
- The number 1 resent of old people is that they didn't do what they wanted in their lives, and rather did what they thought was EXPECTED from them, which a lot of times means doing what gets you money.
- You will...