Recent content by AmanWithoutAscarf

Thank you. From my understanding, as a result, all concentric circular lines will be symmetrically equipotential. Therefore, the radial components along these lines will have the same magnitude, making it unnecessary to prove the second statement Can someone confirm if this is correct?

Originally, from the top view, the illustration is: I mean, it's re-drawn exactly as the paper version And the description of the problem is perhaps like that. Can you show the illustration of your version, please? @Aurelius120

Oh thank you. I found this problem written in my first language, it was part of a big question on a physics test, so I had to translate it back into English here. Sorry for the mistake.

Problem: An annular disk consists of a sample of material with thickness d, inner radius ##\displaystyle R_{1}##, outer radius ##\displaystyle \ R_{2}##, and electrical conductivity ##\displaystyle \sigma##. Let the radial current ##I_0## flow from the inner periphery to the outer periphery of...

Well, honestly, these Nabla symbols always seem scary to me, as a high school student. But if this is the only solution, I will try to learn it. Thank you so much for your sharing!

I'm sorry for the confusion. I assume that the internal magnetic field is uniform, similar to the model of a dielectric sphere in a uniform electric field. This is because the magnetic permeability (##\mu##) of a paramagnetic sphere and the electric permittivity (##\varepsilon##) of a dielectric...

Some special characters were lost during transmission, causing these such chaotic sentences. I'm sorry for this mistake. This is the rewritten version: Here, there is a dielectric sphere oriented in uniform electric field ##E_0##. We can find out the electric fields inside and outside by...

I apologize for any misunderstanding. The second picture is actually about a conducting shell (like a hollow ball) to show a possibility of modeling the external magnetic field as if it was caused by a magnetic dipole moment inside. The third one is the paramagnetic sphere we were talking about...

I believe there is an elementary way to solve this problem using some analogies with relevant models. First, I consider an electric model of polarization in uniform field. Here, there is a dielectric sphere oriented in uniform electric field ##E_0##. We can find out the electric fields inside...

So if I apply Carnot cylcle with the driven force from surface tension, the efficiency will be: $$\eta =1-\frac{T_{2}}{T_{1}} =\frac{W}{Q_{H}} =\frac{\int _{S1}^{S2} \sigma ( T) .dS}{\int _{T1}^{T2} C.dT}$$ Suppose the system witnesses a minimal change in temperature ##dT## when it is stretched...

If you're looking for the quantum nature of that energy, I'm afriad that I'm not able to answer yet. However, from the semiclassical perspective, I believe this amount of energy is equal the total sum of all types of potentials exerted on the emitting electron by the crystal lattice, the atomic...

I think ##hv_s## is the amount of energy required for an electron to be emitted from its crystal lattice. ##hv## is the energy of the photon, which eventually transfers to the electron; if this energy is greater than ##hv_s## and there is no conversion into thermal energy (or other types), the...

The translated version is: 1. 2. I did research on the topic and the Eötvös rule, but most of the results are just qualitative explanations or experiment-based proofs of the temperature-dependent function of surface tension. Can anyone give me some hints on how to prove that linear...

Wow, thank you so much!

I did try to solve the differential equations. From the given assumptions and the second Newton law, we can set up two equations: $$\dot{q} =\frac{S}{\rho }\left( v.B-\frac{q}{S.e}\right)$$ (1) $$\dot{v} =g-\frac{B.d.\dot{q}}{m}$$ (2) Take the derivative of (1) over time, then substitute to...