All Questions
Tagged with time classical-mechanics
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I need an explanation for the time derivative omissions when solving for the Lagrangian of a system [closed]
So I have been self-studying Landau and Lifshitz’s Mechanics for a little bit now, and I have been working through the problems, but Problem 3 is giving me some trouble. I solved the Lagrangian ...
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Does Hamilton's principle allow a path to have both a process of time forward evolution and a process of time backward evolution?
This is from Analytical Mechanics by Louis Hand et al. The proof is about Maupertuis' principle. The author seems to say that Hamilton's principle allow a path to have both a process of time forward ...
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Can I find $\frac{dm}{dt}$ where $m$ is the relativistic mass of a particle?
So, recently I learned the basics of Special Relativity, and I found out that the mass of a body increases with the increase in its velocity as given by the Relativistic Mass equation:
$m=\frac{m_0}{\...
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What to do when the time interval is negative? Should its magnitude only be considered or should it be rejected?
Two bodies are dropped from the same point at different times. I am asked when they meet. The answer I get is -4 seconds. How do I interpret this?
I think that a time interval $t_2-t_1$ always has to ...
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Intuition behind energy not being conserved in Rheonomous mechanical system [closed]
firstly, this is what Rheonomous System means. So, in such a system, the kinetic energy is not exactly just a quadratic function of generalized velocities because one of the generalized coordinates ...
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Why is clock synchronisation such a big deal in physics?
I was reading Classical Mechanics : The theoretical minimum by Leonard Susskind, and he says
Assume that two clocks at different places can be synchronised.
I don't understand why one should do that....
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Experimentally relevant example of a time dependent Lagrangian [closed]
Usually in a classical mechanics class, the Lagrangians are time independent and hence have a conserved energy. Occasionally, a teacher writes down a contrived example with a simple time dependence ...
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Why do none of the fundamental forces depend on a time variable?
As far as I have observed, all the expressions for fundamental forces (at least in Newtonian Physics and E&M) have no explicit dependence on time. Why is this?
For eg: Electric force depends on ...
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Integration of Infinitesimal Canonical Transformation
Let us assume that the transformation $\underline{\zeta(t_0)} \to \underline{\zeta(t)}$ is canonical and suppose that an Infinitesimal Canonical Transformation (i.e. something like $\underline{\eta} \...
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A doubt regarding $L=T-V$ and explicit time dependence
Edit: After having some clarity, I chose to write an answer instead of editing the question itself. Scroll down to read it after reading the problem that follows.
Let's say $\vec{r}=\vec{r}(q_1,q_2 ......
user292464
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What is the domain of definition of time $t$ in physics?
Time $t$ is often used as variable of physical quantity, like $E (r, t)$.
In most EM, acoustic and other wave tutorials, equations (maxwell’s equations, acoustic equations, …) and wave function (EM ...
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Is the speed of objects in time, in Galilean Relativity, a constant and invariant speed relative to all reference frames?
(This question is only about Galilean Relativity. Not Special or General relativity.)
Question: Is it true that every object in the universe, according only to Galilean Relativity is traveling in time ...
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Confusion between implicit and explicit dependence, and its interpretation of the Lagrangian
I just want someone to confirm if whatever I'm writing down is correct or wrong.
If the Lagrangian is given by $L(x,v,t)$, then we say that it explicitly depends on time.
Here, $x$ and $v$ are ...
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3
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What's wrong with this "proof" that all Hamiltonians are time independent?
The time evolution of a system in classical mechanics is given by the solution of Hamilton's equations of motion, which tell us that
$$\frac{\mathrm{d}p}{\mathrm{d}t}=-\frac{\partial H}{\partial q},\...
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How do we measure time?
I'm having a little trouble trying to put to words my problem and I apologize in advance for any causation of trouble in trying to interpret it.
We define periodic events as those events that occur ...
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