# All Questions

2 views

### Is a magnetic field stable?

Is the magnetic field of a magnet stable and not vibrating? Under what conditions does it get unstable?
6 views

### Why should the Planck constant be a constant throughout all space?

Our value for the Planck constant $h$ can be found on experiments on Earth, but how do we know that the Planck constant doesn't change throughout space, for instance it depends weakly upon the ...
6 views

### Finding the minimum energy of an electron in a one dimensional box

I'm told to find the minimum energy of an electron in a one dimensional box of size 1 nm. I assumed first to use the formula $$E = \frac{\hbar^2}{2mL^2}$$ where $L=1\times10^{-9}\,\mathrm{m}$, and ...
7 views

### OPTICAL PATHWAY FOR 10X MICROSCOPE?

How to design an microscope optical pathway using 2 lens for 10x magnification? Help me with the basic pathway drawing and the magnification calculation steps. Thanks in advance!!
85 views

### How do I compute the angle needed to have a turning radius of $<8m$ and its wheel base with 20'' tire

I was doing a project of a vehicle, I'm assigend to the steering. I need to have a turning radius of $<8m$ however I'm limiting my space for the wheels. I've read that $>$ wheel base $=$ $>$ ...
23 views

### What does $\mathbb{R}^3$ and $\mathbb{T}^3$ look physically for the Navier-Stokes equation?

What does the Navier-Stokes equation solution according to the Clay Math Institute look like in real life? As in how do you visualize $\mathbb{R}^3$ and $\mathbb{T}^3$ without the math? I actually ...
5 views

### Finding the resistance of platinum wire

Im currently lost on solving this potentially simple electricty question and was wondering if anyone in this community could hint me or tell me which equations i should be using to solve this ...
7 views

### Is there any experiment which can superimpose neutral particles with radio waves?

I just want to know if there is any experiment done in which a neutral electron and radio wave is superimposed..like both show the dual nature of wave and particle...in future will we be able to ...
47 views

### A derivation in Schwinger's proper time approach

I have a question in derivation of Schwinger's proper time method in chapter 2.1 of http://link.springer.com/book/10.1007%2F3-540-45585-X from Eq.(2.20)-Eq.(2.23) to the classical action expression ...
34 views

### Can I define the term energy in terms of work?

Recently, I'm doing my personal task which is to formalize every definition and concept in physics, by means of formal language and of course with intuitional notes. Because I found myself that the ...
13 views

### Magnetic field in-between two antiparallel wires with the same current

If I have two antiparallel wires with the same current at distance $2a$ apart from each other, how would I go about modeling the magnetic field in between the wires? I know the fields will add but I'm ...
22 views

### Faraday's law and potential along a closed curve

$$\int(\nabla \times \vec{E}) \cdot d\vec{S} = \oint \vec{E}\cdot d\vec{l} = -\frac{\mathrm{d} \phi_b}{\mathrm{d} t}$$ The second expression is the potential difference along a closed curve. Isn't ...
6 views

### How to find the height of a cliff?

I need guidance with the following question: A boat is $50.0m$ from the base of a cliff, fleeing at $5.00m/s$. A gun mounted on the edge of the cliff fires a shell at $40.0m/s$ and hits the boat ...
31 views

### Importance of Schrodinger equation

Louis de Broglie suggested that for microparticles like electrons, wave-like properties can be applied in order to explain some phenomena. Schrodinger wrote down an equation, a wave equation, ...
9 views

### What will happen if there is large amounts (massive) of electrons in a region?

For large amount of hydrogen, they will be bound by gravitation force, start fushion and become a star, how about electrons? Will they also "fuse"?
13 views

### Could an Alcubierre Drive modify a gravitational field?

I'm a high school student, so I have no clue if warping spacetime has any effect on gravitational fields, but the two seemed to be linked based on what I've watched and read. And if a warp drive is ...
99 views

### Pauli Villars Regularization

Consider the t-channel diagram of phi-4 one loop diagrams. Evaluated it is, with loop momenta p, $\frac{\lambda^2}{2}\displaystyle\int\frac{d^4p}{(2\pi)^4}\frac{1}{(p+q)^2-m^2}\frac{1}{p^2-m^2}$ If ...
13 views

### What is wave particle flip flop?

What is wave particle flip-flop and what is its history? Is it related to dual nature of radiation and matter?
14 views

### How to evaluate energy conservation for magnetization?

A permanent magnet can attract a certain magnetic material mass, giving a certain amount of energy $U_{mag}$. If we first use this magnet to magnetize $n$ ferromagnetic pieces, we would have $n$ ...
5 views

### Electrical conductor in a non-conservative electric field

Does electrostatic shielding hold for non-conservative electric fields? I don't think so, but I cannot explain why. Please help.
25 views

### Differential equation for velocity regarded as a function of distance

Given a differential equation for velocity, $dv/dt + v = 1$, as well as its solution, is it possible to derive a differential equation for velocity with respect to distance? I found a solution to the ...
38 views

### why do coiled wire create so much heat?

I am wondering how coiled wire creates so much heat when a current is passed through it. Is it just a larger surface area of heated substance is available or are interacting forces at work eg ...
55 views

### Operator vs. Matrix in quantum formalism

We use in Dirac formalism of QM the tool of operators and kets in spatial and spin spaces to obtain eigenvalues and eigenkets. But the operation here is simply that of a matrix multiplication. Now ...
1k views

193 views

### Half-atwood machine with accelerating pulley

This is a follow-up to my previous question, in which I am now trying to calculate the acceleration of the cart (as before, the block surfaces are frictionless). The mass $m_2$ is attached to $M$ via ...
52 views

### Relativistic approach of a car and a train to a crossing: seeming contradiction

Suppose a car is approaching a railroad crossing at a high relativistic speed, while on the tracks, a square rail car is also approaching the crossing at the same speed. (The road and the railroad ...
17 views

### Cue ball Questions: [on hold]

Note: This question is NOT a homework problem--it is to help me to begin to understand basic physics though a practical approach. If a 170g cue ball was at rest on a flat, smooth surface, how would ...
204 views

### Liquid column “recoils” in a sealed cylinder when hit by a piston — is it possible?

Consider a cylinder filled partially with a liquid (e.g. water). The cylinder is sealed, and is at held at room temperature (e.g 298K). At equilibrium (or when no external disturbance is imparted to ...