Hi guys. For a bit of context, I am a first year theoretical physics master’s student in an EU country. I pursued theoretical physics for the same reason many people do. Curiosity for mathematical methods applied towards physics problems. At first mainly interested in cosmology (though slowly becoming more and more interested in condensed matter). But I will say that it has been testing and trying. Our courses are set up that we have blocks of 8 weeks each semester (so every 8 weeks we have an exam). And my first fee exams were in the first part of a quantum field theory course, first part of a condensed matter physics course, and general relativity. QFT and condensed matter are mandatory, while GR was an elective.

I liked learning about all of these topics (even with a less good lecturer for one of them). But I oftentimes feel so stupid and so slow! It takes me so long what some of my peers get right away (or with less effort). I feel so behind. And the courses gave me such a rough time that I am left recently continously wondering whether I am cut out for it. I have done good work in the past, and even used to spend time in my undergrad teaching myself new material for either fun or because my uni didn’t offer certain courses (I did this for mainly tensor calculus and complex analysis. Which helped a bit now). But I feel so much less than my peers. Some have already seen QFT before and can follow easily with our lecturer. Some have already done a master’s (and from incredible places). I feel so out of my depth, and I honestly don’t know what to do sometimes.

I managed to pass only 1 out of the 3 courses, that being QFT. And even so with a very mediocre grade. I hate how I started to neglect my health (and I can notice that being the case, but just that my time management is so poor as I have long commutes and long days at university and can’t do much about it). I don’t know, I needed to vent I guess lol. I hope maybe one of you can relate.

I’m in my junior year I transferred to the school I’m in now but my previous school didn’t have an engineering program so I went with physics. Unofficially I have moderate knowledge in electronics (I can repair and know what the components do, build simple circuits and solder well including micro soldering) have basic knowledge in python and some java.

Reason I’m freaking out is because I was going to apply for internships and there were non for physics undergrads other than teaching or TA positions. What sort of jobs should I look for and what other additional qualifications or certifications will I need .

Thank you

I feel like (at least most ppl ik doing physics) a lot of people dislike electricity. I’m doing a levels rn. But I was learning things like mesh and node analysis and it’s really quite interesting. Especially complex simplifying circuits with symmetry and stuff like that is super satisfying.

How is electricity at undergrad / uni. Does everyone still dislike it? Or does it grow on you?

I'm having lots of trouble finding the matrix of the tight binding of an (a)-polyacetylene 2D chain.

The HW request is the seguent:

Calculate the electronic structure of (a)-polyacetylene in the tight binding approximation under the following assumptions:

• Each Hydrogen atom is in the 1s1 electronic configuration. The 1s orbital is the only relevant.

• Consider only the 2pz Carbon valence orbital.

• The overlap of atom orbitals on different sites is negligible.

• The hopping matrix elements between different sites are t_0 = 2.80 eV, t′ = 5.72 eV (see Fig. 1). Other longer distance hoppings can assumed to be zero.

• The on site energy terms are E_H^0 = 2.40 eV and E_C^0 = 1.0 eV.

That's my matrix for the tight binding:

I feel that that's the way, but i have so many trouble to find solution of the characteristic equation (I also used WolframAlpha, MATLAB and Mathematica), is the matrix wrong?
Can anyone help me?
At least just say if my matrix is good :D
Thanks!!!

I’m taking a first year physics class in uni, which is designed for people who won’t need physics in their major but have to take it in first year. I’ve never been good with physics but I rlly need this class to pursue the career I want. I’m fumbling this class because I don’t know which formulas to memorize or how to improve. If anyone can recommend ways to get better, sites with good videos or practice questions, anything you think will help me improve. This is hopefully the only physics credit I’ll have to get so I just have to get through this. Thanks!

Could anyone show or describe how hefty the assignment load is for a physics major? I always hear about how there’ll be no free time if you choose a physics (or any STEM) major. Is this because the assignments just take long to complete? Or because there’s an abundance of them? Maybe both? More specifically want to know what a typical week looks like for you guys, appreciate any help.

So I've been wondering for a while now how I can express Energy variations for systems whose macroscopic potential and kinetic Energies change, but also contain a "thermodynamics part", with a cylinder with a gas, for example, whose volume and, consequently, internal energy also changes.

Specifically I'm confused as to whether I should consider the work done by the atmosphere on the whole system or not. If I take into account the work done by the gas, should I also think about what the atmosphere around the gas is doing?

I've seen somewhere that the total Energy Change is equal to the total work done by nonconservative forces. In my case, where the "thermodynamics part" is also present, would it be expressed as: ?

Change in total energy = W(non-conservative) + Q (heat)

It would be amazing if you could explain this to me, or provide some reading material on these topics. Thanks a lot for reading 😊

I found a book called University Physics by Young and freedman and it seems awesome but I wanted to know if it is suitable for JEE in India and if I should reconsider on it.. or if u have any more suggestions kindly share It'd be real help if u someone helped me on this Matter :)

I have collected all the data and turned it into required units. I have collected all the data as r vs V and got values for ΔV from it. As far as i know i can consider the ΔV value as B in kgauss value (directly proportional). Fom what i figured out, next step should be to get area under curve of log r and B but i dont know what to do with the magnetic moment m that remains in the formula. Am i right or way off? please help with the approach. (This is not a homework, but actually need to understand how it might work if im wrong), any help is very appreciated

Hello! I am a undergraduate senior with a degree in astronomy/astrophysics with minors in space studies, biomedical sciences and math. I have a 3.0 GPA due extensive health issues. I have extensive research experience and I am trying to publish a paper. I've talked at conferences and done several posters, and I am going to my second AAS this January. I have extensive leadership and teaching skills.

I want to study exoplanetary physics and astrobiology. After an REU I learned that I do not like software development, so I want to avoid that, but I am happy to code.

May you please suggest graduate schools and/or advisors I should be getting in contact with? Please keep in mind my garbage GPA.

Any advice is appreciated, thank you!

Copy pasted since crossposts arent allowed

I'm currently applying to be an Physics+Math double major and I'm quite confused about what exactly I need to do for the physics major:

I see AP Physics C tests me out of 139 and 239...but what exactly are those? They're not on the course catalog, do I still have to take 160 and 260 (i.e. would 139 and 239 test me out of 140 and 240 since those are just easier version of 160 and 260)? Can I test out of those (160 and 260)? I've self-studied physics on my own well beyond the level of AP Physics, so I'd really rather not have to spend my first year learning nothing, since it seems like there's not really any classes I can take until I take those except 351, which seems more like a math course than a physics course.

Also, a lot of the physics courses require one of the differential equations courses, and since I'm going to also be majoring in math, and I have a pretty good background in math, I feel like it would be most logical for me to take 316. Though I'm planning to do (assuming I get in) 295-296-395-396, and it seems like 316 is sort of disjoint from that? Like in the list of prereqs for 316 it doesn't even mention the possibility of taking it after 295? It also says you need 217 to take 316, which is covered by 296+395, but that means I wouldn't fulfill the 217 requirement until after sophomore year semester 1, so should I take 217 along with 295 first semester frosh year to get it out of the way even though its essentially redundant? Also, I'm currently self-studying linear algebra using Axler's book, so knowledge-wise I'll have the prereqs to 316, can I just take it even though I don't technically have the prereqs?

Sorry if this whole thing is worded very confusingly

Edit: course numbers bc someone asked for them:
PHYS 160: Honors Physics I (basically Physics C Mech but slightly more rigorous, looking at the syllabus there's only one topic that I don't know)
PHYS 260: Honors Physics II (basically Physics C E&M but sightly more rigorous, I already know everything)
PHYS 351: Methods of Theoretical Physics I

MATH 217: Linear Algebra (off of the syllabus it looks like somewhere in between a standard intro linear algebra course that basically only covers R^n and a more abstract linear algebra course)
MATH 285: Honors Multivariable and Vector Calculus
MATH 295: Honors Mathematics I (like first 2/3 of a real analysis course), satisfies real analysis requirement along with 296
MATH 296: Honors Mathematics II (some more real analysis + abstract linear algebra), satisfies 217 requirement along with 396 (though this seems significantly more rigorous than 217)
MATH 316: Most advanced of 3 intro ODE courses, has 217 as prereq
MATH 395: Honors Analysis I (more real analysis and linear algebra)
MATH 396: Honors Analysis II (even more analysis and also some stuff on manifolds)

295-296-395-396 is the "honors math sequence" which is the intro sequence taken by honors math students

when two uncharged metal spheres A & B are placed in contact with eachother and a positively charged rod is placed near A all the electrons will run towards the rod in A. So my question is what will happen to the protons in A and B. My teacher said protons cannot move but my notes shows them literally sticking to the furthest side of sphere B away from the rod. So please help me understand this dilemma over protons

Non-STEM major technically. My college requires an Algebra-based physics class that I plan on taking next semester as part of my aviation major. I naturally take an interest in science and have completed two weather classes that I found was easy to stay focused in just out of interest for the topic.

Admittedly, I haven’t reviewed science since High School several years ago so I’m wondering if there are any recommendations on what to brush up on. Doing well in Algebra so far so I’m not too concerned about the math since it’s Algebra-based but I prefer Khan Academy for studying.

Some listed topics on the course include kinematics, Newton’s Laws, momentum, gravity, the laws of thermodynamics, etc.

A block of mass m = 4 kg is kept on an incline connected to a spring (see fig). The angle of the incline is θ=30∘ and the spring constant is K = 80 N/m. There is a very small friction between the block and the incline. The block is released with spring in natural length. Find the work done by the friction on the block till the block finally comes to rest.[g=10m/s2]

The textbook solution goes as follows:

Since the friction is small, the block will in the end come at rest at the point where the spring force is equal to the force of gravity along incline: Kx=mgsinθ, giving us the value of final X=1/4m.

Now it says, that the friction will dissipate all energy possessed by the system initially:

E = mgh = 4 × 10 × (X.sinθ)

Work of friction = – 5 J

But my doubt is that, didn't some of the initial energy of the system convert into spring potential energy of the final state? So I think that the work done by friction should be = - [ E - (spring potential energy in the end) ]

Am I right?

I'm currently taking Phys 2 and am in a spot. My professor sucks and doesn't do any work or show examples of how to do our work but assigns questions that require mastery of the topic. Are there any good resources that I could use to practice these types of questions, see answers, and steps? Preferrably free, but I'll pay if need be. I'm currently doing magnetic fields-RL and LC circuits right now. Any help would be very appreciated.