# Tagged Questions

Questions related to mathematical physics which include application of mathematics to problems in physics and the development of mathematical methods suitable for such applications and for the formulation of physical theories

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### Describe a sine wave of known frequency with only two points

This is my first post on math.stackexchange (sorry if meta people remove the Hello (sometimes we do that over on stackoverflow ;P)! I have a system wherein I know that the output is a sine wave, with ...
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### Work done by a force Field

Homework for Calc III includes a problem about computing the work done by a force field (defined by a specific vector equation) on a moving particle. I was attempting to compute this using the ...
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### Trouble understanding a common vector calculus example

I have difficulty understanding the following vector calculus example. Text can be found here. It is the 5th Q&A -- starting with equation (31.1035).It concerns finding the vector potential of a ...
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### Reflecting a golfball off a wall to a hole and compensating for the balls radius

Problem: I'm struggling to compensate for the radius of a ball when reflecting it off a wall towards a target. (sorry I cannot yet post images) What I want is to do this: golf reflections but this ...
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### Solving a simple equation

I am just starting to study physics and I found this equation: $$\ x = 8 - {6t} + t^2$$ If possible please explain in a step by step. Sorry if it's too simple.
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### Minimum Ejection Velocity

PROBLEM: Calculate the minimum ejection velocity with which a shell must be fired to strike a target 1000ft high and directly overhead. QUESTIONS: I use integration to work back from 32ft/sec and ...
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### Up and Down Motion (Two objects meeting in time?)

PROBLEM: Suppose than an object is thrown upward with an initial velocity of 200ft/sec and that another one is thrown upward 5 seconds later with an initial velocity of 300ft/sec. When and where do ...
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### Self-learning; Physics and Mathematics

My fields of interest are Physics and Mathematics. Gerard t'Hooft, 1999 Physics Noble Prize Laureate, has suggested a better scheme to study physics online. I can't wait for the university, so I've ...
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### Where do I go from Linear algebra past Calc III to try to learn complex physics (relativity and quantum group theory)?

I'm mainly a programmer, but I have a love for Mathematics that's been, well, insatiable. I've had my eye on learning Quantum Groups and Relativity, but I want to stay in something I can do with ...
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### Can rainbows be considered to have mathematical patterns?

Of course it is evident that there is physics and mathematics involved in a rainbow, but my question is (as the title suggests) are there patterns to be found in rainbows? By patterns I mean ...
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### Moment of inertia of a circle

A wire has the shape of the circle $x^2+y^2=a^2$. Determine the moment of inertia about a diameter if the density at $(x,y)$ is $|x|+|y|$ Thank you
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### Degree of maps on the 3-sphere

I am currently in the process of going through Ticciati's Quantum Field Theory for Mathematicians, which states the following (Theorem 13.7.11): "Let $g$ be a differentiable function from $S^3$ to a [...
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### Resonance Frequencies of Oscillator

I understand that resonance is when the force term increases the natural oscillation of the system. In the next equation the oscillator has a natural frequency $\omega_0=\sqrt{\frac{k}{m}}$. But I don'...
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### Coordinate Transformation on Local coordinate system

I am having a point $P(x,y,z)$ in $3D$ with respect to global coordinate system. I want to create an another Local Coordinate System by picking three points $N1, N2, N3$ in 3D. Now I want to know the ...
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### Geometry brain teaser (Candle in the room with mirrored walls)

King wants 2D room with smooth walls and columns (second derivative exists) that reflects light. King asks you to build it in such way that there exists a spot, where you can place a candle and there ...
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### Electrostatic Potential Energy

How is the boxed step , physically as well as mathematically justified and correct ? Source:Wiki http://en.wikipedia.org/wiki/Electric_potential_energy As work done = $- \Delta U$. for Conservative ...
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### Find the time at which a particle projected up an inclined plane, comes to rest?

A particle of mass $m$ is projected up a plane that is inclined at an angle $\alpha$ to the horizontal. At $t=0$, its velocity is $v_0$ and the coefficient of dynamic friction of the slope is $\mu$...
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### Difficulty in obtaining the Lorentzian lineshape for natural broadening

Not sure if this maybe belongs more in the maths section, but since it comes from a physics problem i'll post here. when calculating the natural broadening lineshape for a laser we have to take the ...
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### Velocity and Distance; Functions of Time

$s(t)$ = distance a particle travels from time $0$ to $t$. If in this case, the distance $s$ is only the function of time then its necessary that the velocity should be constant. Likewise, $v(t)$ = ...
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### Distance of a particle; a function its time

Force is a function of mass and acceleration. Here mass is a fundamental quantity, and acceleration is a derived quantity OR $F(a, m) = ma$. I want to ask that why the distance traveled by a ...
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### What is this physicist saying?

I do not want to poison this forum with politics. But I want to understand, precisely, what is meant by the bolded statement. It is made by a physicist who used to work at Harvard regarding the ...
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### Let $F(x,y,z) = -c(r/||r||^3)$ be the force resulting from the inverse square law…

$c$ is a constant and $r = (x,y,z)$. Show that $\displaystyle f(x,y,z) = \frac{c}{\sqrt{x^2+y^2+z^2}}$ is a potential function for $F$. What can be concluded from any path from point $A$ to point $B$ ...
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### Calculating the angular velocity

I have an inverted pendulum with a accelerometer mounted on the top that at rest gives me a vector up opposite to gravity, which is used to calculate the angle of the pendulum. Is it possible to ...