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1 vote
0 answers
47 views

Find curve minimizing energy loss due to friction [closed]

I am looking for an ansatz of the following problem: Given a mass $m$ moving in a constant gravitational field along curves $C$ connecting two fixed points I want to find the curve $C_0$ that ...
TomS's user avatar
  • 907
3 votes
1 answer
123 views

What is the definition of a Brachistochrone curve in a non-Euclidean space?

I have a problem where I have to study "the geometric properties of the Brachistochrone curve in non-Euclidean spaces". But I am confused about the definition of the Brachistochrone Problem/...
Karl's user avatar
  • 31
1 vote
2 answers
135 views

Evaluating the integral in the brachistochrone problem numerically

When solving the brachistochrone problem (path of least time for a mass sliding on the path, with the path having no friction, from point A to point B), the solution curves are solved from the ...
Ville Alanko's user avatar
0 votes
1 answer
102 views

For virtual displacement in the Lagrangian, why is $\delta \dot{x_i} = \delta \frac{dx_i}{dt} = \frac{d}{dt}\delta x_i \equiv 0$?

I am having trouble understanding why $$\delta \dot{x_i} = \delta \frac{dx_i}{dt} = \frac{d}{dt}\delta x_i \equiv 0.\tag{7.132}$$ you can see my explanation leading up to it below. I would greatly ...
Reuben's user avatar
  • 283
2 votes
2 answers
273 views

Brachistochrone to a vertical line [closed]

Just for fun, I am working through some problems in Mathematics of Classical and Quantum Physics by Byron and Fuller. Problem 2.13 reads: Prove that a particle moving under gravity in a plane from a ...
OmnipotentEntity's user avatar
9 votes
1 answer
962 views

What is the intuitive reason that the trajectory of a charged particle in a uniform crossed electro-magnetic field is a brachistochrone?

Cycloid is a type of trajectory which is traced by a point on the circumference of a planar circle rolling without slipping on a surface. It turns out that this is the solution to the Brachistochrone ...
kbakshi314's user avatar
  • 2,402
3 votes
3 answers
427 views

Lagrangian Derivation of Brachistocrone? [closed]

I've been trying to derive the functional description of the brachistocrone. To do this, I used the Lagrangian to describe motion along a functional path. given a function $ f(x) $ where $0<y<a$ ...
BooleanDesigns's user avatar
5 votes
0 answers
101 views

Optimal tunnel shape for travelling inside the earth [duplicate]

Say you were to travel from Paris to Tokyo by digging a tunnel between both cities. If the tunnel is straight, one can easily compute that the time for travelling from one city to the other (...
Mathusalem's user avatar
0 votes
1 answer
7k views

Why is a cycloid path the fastest way to roll a ball downward? [duplicate]

Possible Duplicate: Path to obtain the shortest traveling time I've been told that if one would want to make a ramp to get a ball from point A to a lower point B (at a certain horizontal distance ...
Edward Stumperd's user avatar
5 votes
2 answers
4k views

Path to obtain the shortest traveling time

Asume we have a particle sitting at the point A(0,0) in a gravitational field. (g=9.81) It is going to move along some path to the point B(a,b) Where a>0 and b<0. What is the curve the particle ...
N3buchadnezzar's user avatar