1. ### I Question about the Equivalence Principle (locally flat spacetimes)

Hi all, I have ran into some confusion about the equivalence principle; perhaps I should state what I understand and then proceed to ask questions. It is my understanding that the equivalence principle states that spacetimes are locally Minkowski, and so the rules of SR apply in that locality...
2. ### Do chemists think differently than physicists?

Summary: Do chemists think differently than physicists? And should I Change my subject in University... Hey guys, I'm asking myself this question in hoping to find myself in life… some advice and ideas would be really helpful. I'm from Europe and I'm actually studying chemistry. I still Need...
3. ### I Pressure differences in a leaking vacuum vessel

Hello all, I'm new to this forum and I'm mucking about with some self-made physics conundrums, and I need some help! So, What I am aiming for is a roughly cylindrical vessel (it can, and I think probably has to, be tapered to achieve the effect) with the air being pumped out of one end, and a...
4. ### I Valence band and Fermi level difference?

I was wondering what the difference was between the valence band and fermi level? How do we distinguish between the two? Thanks in advance.
5. ### I Mixed states vs pure states - physical POV

Hey guys, I am having issues with understanding the physical nature of pure and mixed states. Maybe you can help me out? 1) A pure state - superposition is a state that consists of different states at the same time. It's like having several waves, each one belonging to an Eigenstate of the...
6. ### B What is the difference between MWI and CI?

Suppose we measure a normalized state ##|\Psi \rangle = \alpha _0 | \lambda _0 \rangle + \alpha _1 | \lambda _1 \rangle + \alpha _2 | \lambda _2 \rangle + ...## with ##| \lambda _i \rangle## the eigenvalues of the measured observable. Is it true that, in the CI, the wavefunction collapses into...
7. ### B Pulses, waves, train waves....

What are the difference between them? What is that one in the photo?
8. ### Solving for Electric Potential Difference in Square diagram

Homework Statement I've attached a url with a picture of the problem setup and diagram https://instagram.com/p/7nYNXTscre/ [Broken] Homework Equations I used the equation V = KΣiqi/ri to solve for potential at A and B The Attempt at a Solution For Va I used K((Q/d)+ (2Q/(d^2+d^2)^.5)) I just...
9. ### Heat energy dissipated between two conducting shells

Homework Statement A conducting sphere of radius a is surrounded by a neutral conducting shell of radius b (b > a).Connections are provided as shown in diagram. Initially, the sphere has a charge Q. The switch S1 is opened and then closed. The switch S2 is then opened and closed. Finally, the...
10. ### Should I memorize all these trigonometric integrals?

I only memorized these trigonometric differential identities : sin(x) = cos(x) cos(x) = -sin(x) because I can convert tan(x) to sin(x) / cos(x) and sec(x) to 1 / cos(x) .. etc And there is no need to memorize some integral identities such as : ∫ sin(x) dx = -cos(x) + C ∫...
11. ### Mathematica question

Homework Statement I draw two 3D graphs in Mathematica by using the "Plot3D "and I want to Show the difference between these two graphs. Can anyone tell me what command should I use? Homework Equations The Attempt at a Solution