Questions tagged [physics]
Questions on the mathematics required to solve problems in physics. For questions from the field of mathematical physics use (mathematical-physics) tag instead.
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Using mathematics in theoretical physics
I'm a non-mathematician who is self-studying mathematics. Although I'm very interested in mathematics, my main purpose is to apply math in theoretical physics. The problem is that when I read a ...
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What Mathematics questions can be better solved with concepts from Physics?
Over the years, I've seen several questions in mathematics that can be solved using concepts borrowed from Physics. Having seen these question, I'm interested to find out what other mathematics ...
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Why is this allowed? ("Fourier's Trick"; finding the coefficients in a Fourier Series)
In my textbook (Introduction to Electrodynamics, D. Griffiths), we derive the equation for some strange potential function. Eventually, we get to this (for $n \in \mathbb{Z}^+$):
$$ V_0(y) = \sum_{n=0}...
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What do physicists mean when they say something is "not a vector"?
It's common for physicists to say that not every 3-tuple of real numbers is a vector:
“Well, isn’t torque just a vector?” It does turn out to be a vector, but we do not know that right away without ...
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Energy norm. Why is it called that way?
Let $\Omega$ be an open subset of $\mathbb{R}^n$. The following
$$\lVert u \rVert_{1, 2}^2=\int_{\Omega} \lvert u(x)\rvert^2\, dx + \int_{\Omega} \lvert \nabla u(x)\rvert^2\, dx$$
defines a norm on ...
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Help with Seemingly Hopeless Double Integral
I hate to be that guy to just post an integration problem and ask how to solve it so I'll give a little relevant info
Okay, so I'm working on a physics project and my professor proposed that the ...
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Books to learn physics, being a math major
What books would you recommend to learn physics, being a a Math major, from classical mechanics, electricity, etc. to modern physics?
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What is the resistance between two points a knights move away on a infinite grid of 1-ohm resistors [closed]
On an infinite grid of ideal one-ohm resistors, what's the equivalant resistance between two nodes a knights move away?
(please fix the tags, I didn't really know where to put it)
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Cross product and pseudovector confusion.
So called pseudovectors pop up in physics when discussing quantities defined by cross products, such as angular momentum $\mathbf L=\mathbf r\times\mathbf p$. Under the active transformation $\mathbf ...
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Coronavirus growth rate and its (possibly spurious) resemblance to the vapor pressure model
The objective is the model the growth rate of the Coronavirus using avaibale data. As opposed to the standard epidemiology models such as SIR and SEIR, I tried to model a direct relation between the ...
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Interpretation of an integral transform from the wave equation to the heat equation
I'm having troubles with understanding the physical meaning of a certain transform.
If $u$ is a solution to the wave equation $$\partial_t^2u-\Delta u=0\
\mathrm{in}\ \mathbb{R}^n\times(0,\infty)\\...
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Geometrical construction for Snell's law?
Snell's law from geometrical optics states that the ratio of the angles of incidence $\theta_1$ and of the angle of refraction $\theta_2$ as shown in figure1, is the same as the opposite ratio of the ...
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Mathematical meaning of certain integrals in physics
While studying on texts of physics I notice that differentiation under the integral sign is usually introduced without any comment on the conditions permitting to do so. In that case, I take care of ...
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Can there be an energetically unbounded three-body orbit where escape is impossible due to conservation of angular momentum?
This question evolved from a discussion below this answer which explains (among other things) that the total energy of a system offers insight as to the possibility of one (or all) members "escaping". ...
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Finding the Center of Mass of a disk when a part of it is cut out.
From a uniform disk of radius $R$ a circular disk of radius $\frac{R}{2}$ is being cut out.
The center of the "cut out" disk is at $R/2$ from the venter of the original disk. We have to ...
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