The classical-physics tag has no wiki summary.
3
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2answers
47 views
Equal mass on either end of a spring
I'm taking physics this term and this is the first time taking physics in 3 years.
Here is my homework question (of course those variables all have values but we'll use variables for now):
Consider ...
0
votes
1answer
72 views
Standing Waves: finding the number of antinodes
A string with a fixed frequency vibrator at one end forms a standing wave with 4 antinodes when under tension T1. When the tension is slowly increased, the standing wave disappears until tension T2 is ...
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0answers
16 views
Acceleration by spherical particles (micron-scale) by an external force
I am looking for an expression for the velocity of a micron sized (1 - 10 micron diameter) sized particles under accelerating forces.
I have aerosols in mind.
This is what I have in mind
The ...
-2
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1answer
53 views
Why is there no such thing as a body in a state of acceleration?
It appears that velocity is a quantity of motion meaning that all objects can have assigned to them a particular velocity. Through the application of forces (ex: gravity, E&m) we measure changes ...
0
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1answer
39 views
Is this a correct interpretation of pressure?
So I am told that pressure = Force per Area --> F/A..
When considering the units of Force I find that force = kg * m/s^2
When considering the units of Area I find that area = m^2
Thus the units of ...
0
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2answers
97 views
Calculating phase difference of sound waves
An observer stands 3 m from speaker A and 5 m from speaker B. Both speakers, oscillating in phase, produce waves with a frequency of 250 Hz. The speed of sound in air is 340 m/s. What is the phase ...
2
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2answers
133 views
Should I use Coulombs law when magnets attract/repel?
When magnets attract to each other or repel.
Should I use Coulombs law? If not, why not?
Some would say that I shouldn't because: "Coulomb's law deals with static charges and force due to them. ...
1
vote
2answers
48 views
effect of vertical collision on kinetic friction and subsequent change in horizontal velocity
Suppose somehow a block of mass $m$ is moving on ground, and the coefficient of kinetic friction between the block and the block is $\mu_k$. If I drop a tennis ball(of same mass) on it from a ...
9
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3answers
435 views
Physical and Geometrical interpretation of Differential Forms
I have a doubt about the physical and geometrical interpretation of differential forms. I've been studying differential forms on Spivak's Calculus on Manifolds, but my real intent is to use those ...
0
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0answers
49 views
Calculating attracting magnets?
I have two identical bar magnets...
Each bar magnet can lift an object with 10lb of force.
When they attract each other, I believe that each magnet applies a force of 10lb to attract the other.
That ...
12
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4answers
456 views
Tree level QFT and classical fields/particles
It is well known that scattering cross-sections computed at tree level correspond to cross-sections in the classical theory. For example the tree level cross-section for electron-electron scaterring ...
8
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3answers
179 views
Is $k_B \rightarrow 0$ the classical limit of stat. mech., as $\hbar \rightarrow 0$ is in QM?
I hear very often among my peers and seniors that just as how $\hbar\rightarrow0$ takes me to classical mechanics from quantum mechanics, $k_B\rightarrow0$ will take me to classical thermodynamics ...
2
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2answers
136 views
Rigid body dynamics of tossing of a coin
While tossing a coin, it is commonly experienced that you get a head, if you toss it up with the head side up, and a tails if you toss with the tails side up. Is there a mathematical proof of this ...
2
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0answers
30 views
One dimensional motion with changing acceleration. Falling to a large body from a great distance [duplicate]
Possible Duplicate:
Radial fall in a Newtonian gravitational field
My math and physics are rusty. I am trying to calculate the time an object takes to fall to a large body. Before you ...
0
votes
1answer
93 views
How to go from Quantum World to Classical World? [duplicate]
Possible Duplicate:
Is it possible to recover Classical Mechanics from Schrödinger’s equation?
Classical Limit of the Feynman Path Integral
In the quantum world we don't have ...
0
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1answer
132 views
Solution of a partial differential heat equation with derivative and boundary conditions
I want to solve the following partial different equation.
Find $u(x, t)$, satisfying $u_t = u_{xx}$ , $u(x, 0) = x − x^2$ , $u(0, t) = T_0$ , $u_x (1, t) = 0$ and $|u|$ is bounded.
Using separation ...
0
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1answer
136 views
Generalized momentum conjugate and potential $U(q, \dot q)$
On Goldstein's "Classical Mechanics" (first ed.), I have read that
if $q_j$ is a cyclic coordinate, its generalized momentum conjugate $p_j$ is costant.
He obtained that starting from Lagrange's ...
1
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1answer
186 views
Non-linear dynamics of classical hydrogen atom
I'd like to know if there have been attempts in solving the full problem of the dynamics of a classical hydrogen atom.
Taking into account Newton equations for the electron and the proton and Maxwell ...
0
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1answer
81 views
Non-linear dynamics of classical hydrogen atom [duplicate]
Possible Duplicate:
Non-linear dynamics of classical hydrogen atom
I'd like to know if there have been attempts in solving the full problem of the dynamics of a classical hydrogen atom.
...
0
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0answers
187 views
Magnetic field in case of 4 parallel wires… [closed]
I'm looking at four parallel wires of finite length L that are assumed infinitely thin. They are arranged in a square configuration and their currents flow in directions as shown in the figure...
...
1
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2answers
207 views
Charge, velocity-dependent potentials and Lagrangian
Given an electric charge $q$ of mass $m$ moving at a velocity ${\bf v}$ in a region containing both electric field ${\bf E}(t,x,y,z)$ and magnetic field ${\bf B}(t,x,y,z)$ (${\bf B}$ and ${\bf E}$ are ...
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3answers
231 views
Do strong and weak interactions have classical force fields as their limits?
Electromagnetic interaction has classical electromagnetism as its classical limit. Is it possible to similarly describe strong and weak interactions classically?
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0answers
78 views
Mathematical Formulation of the laws of classical physics
By classical here I mean non-quantum mechanical, and everything that is developed afterwards such as color, etc.
I am wondering if we can look at our Universe mathematically like this:
Let ...
4
votes
1answer
368 views
Deriving the action and the Lagrangian for a free particle in Relativistic mechanics
My question relates to
Landau, Classical Theory of Field, Chapter 2 - Relativistic Mechanics, paragraph 8 - The principle of least action.
As stated there, To determine the action integral for a ...
1
vote
1answer
142 views
On the Discretization of Energy Levels
We consider a system of "n" particles whose total energy E and net momentum $\vec{P}$ are fixed are fixed.There no net force on the system(assumed)
$$\Sigma \epsilon_i= E$$
...
3
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3answers
459 views
Rotational speed of a coil in a uniform magnetic field at equilibrium
I'm looking at the following problem from "Physics 3" by Halliday, Resnick and Krane (4th edition):
The armature of a motor has 97 turns each of area 190 cm² and rotates in a uniform magnetic ...
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1answer
113 views
When does/doesn't a classical physical/mechanical system need to be known, given, defined? [closed]
My question is at the same basic but perhaps quite deep.
It is motivated by the fact that I've been unable to find a clear mathematical definition of a system in classical physics/mechanics.
It runs ...
0
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0answers
84 views
Aerodynamic drag on a cannonball?
I'm trying to build a ballistics simulation where I shoot a cannonball. I want to allow for drag and am trying to work out the math to do so.
I can work the drag out using $F = Cd\times S\times ...
2
votes
0answers
114 views
Functional determinant approximation
Let the Hamiltonian in one dimension be $H+z$, then I would like to evaluate $\det(H+z)$.
I have thought that if I know the function $Z(t) = \sum_{n>0}\exp(-tE_{n})$ I can use
$$\sum_{n} ...
3
votes
2answers
115 views
Interacting classical strings?
May classical strings be interacting?
I would guess no, I can not see any way to break a classical closed string in two of them (the "pants" diagram); but maybe I'm missing something.
