# Tagged Questions

The tag has no usage guidance.

59 views

### Odd question on potential energy [on hold]

A particle with mass $m$ is acted on by a conservative force and moves along a path given by $x = A\cos\omega t$ and $y = B\sin\omega t$, where $A$, and $B$ are constants. Find the potential energy of ...
36 views

### Field energy - classical electrodynamics [on hold]

I was trying for few hours to prooved one thing: If we know that energy of the field is given by equation: \varepsilon = \frac{1}{8 \pi} \int ( {\bar E}^2 + {\bar H}^2) d^3 {\bar r} ...
263 views

### Oscillation of a Bose Einstein condensate in a harmonical trap

We were asked to try to make a theoretical description of the following phenomenon: Imagine a 2D Bose Einstein condensate in equilibrium in an harmonical trap with frequency $\omega$. Suddenly the ...
9k views

15 views

### How to determine time of dephasing?

Let's assume that I have an oscillating value A. After some time the oscillations are being damped so the diagram of A is like on the picture below: Now how to determine when does the A is reduced ...
21 views

### Is it possible to determine when an accelerometer is in a vibrating state compared to a non-vibrating state?

I would like to know if so, how raw 3-axis accelerometer data could be analyzed and manipulated real-time to register periods of vibration. The device being used has a max sample rate of 62Hz (I ...
30 views

### Expansion in differential equation (rapid oscillating field) [closed]

Can anyone explain me how to derive the equation in (30.4)? I don't understand what approximations or substitutions are exactly performed.
83 views

### Pendulum's motion is simple harmonic motion

For a pendulum's motion to be simple harmonic motion (S.H.M.) is it necessary for a pendulum to have small amplitude or S.H.M. can be produced at large amplitudes as well? If it is really necessary ...
678 views

### What is a mode?

Admittedly, this seems like a very simple question. The word mode pops up in every field of physics, yet I can't remember ever having read what I felt was a precise and sensible definition. After ...
58 views

93 views

### Why is a sine wave considered the fundamental building block of any signal? Why not some other function? [closed]

It is mathematically possible to express a given signal as a sum of functions other than sines and cosines. With that in mind, why does signal processing always revolve around breaking down the signal ...
28 views

### What determines the point of energy spillover to higher modes of a standing wave resonator?

One of the better known physics demonstrations for standing wave resonance is the singing rod . By holding the rod exactly in the middle the demonstrator constrains the first mode of excitation - the ...
60 views

### Kater's pendulum graph

I was told that the graph of position vs period must be a straight line in Kater's pendulum, but my findings are more curved, also after searching in google graphs are like parabolas, my question is ...
630 views

### Small oscillations of heavy string

I'm solving problem in classical field theory and I have some difficulties. I'm trying to study small oscilations of heavy string with fixed points. First of all I wrote down this Lagrangian: ...
335 views

### Are there any fully analytically solvable nonlinear oscillators?

I'm trying to find a simple one-dimensional problem, in which a particle would oscillate with some energy, and the period of oscillation would depend on particle energy (unlike in harmonic ...
A homogeneous, spherical electron cloud describes an atom (radius $a_0$ and total charge $^−e$ and positive point charge$^+e$ as the nucleus. An external electric field stimulates the electron ...