# Questions tagged [dissipation]

The tag has no usage guidance.

490 questions
Filter by
Sorted by
Tagged with
24 views

### Friction on a rolling body [duplicate]

I have been reading about rolling motion and I seem to have a confusion regarding the friction acting on such bodies. First off for a body to start rolling their has to be some friction b/w the ...
1 vote
162 views

### If energy is conserved, why do we need to save energy?

The conservation of energy says that it can neither be created nor be destroyed, it can only be transferred from one form to another. i had this doubt in my mind for a long time that why do we need to ...
21 views

### Fourier Transform of Damped Oscillations - Zero Frequency Peak and Shift [duplicate]

A damped oscillator has the time evolution: $$y(t) = e^{-\Gamma t}\cos^2(\tilde{\omega}_0 t)$$ where $\Gamma$ is the damping rate, $\tilde{\omega}_0^2=\omega_0^2-\Gamma^2$ and $\omega_0$ is the ...
9 views

### How to determine structure stiffness of a damped 1D system with acceleration - time graph?

Consider a damped system with only acceleration - time data is available, how to determine the structure stiffness (k)? Mass of the structure is also known. It moves in a horizontal direction, like a ...
1 vote
70 views

### Equations of motion for two masses connected by the Kelvin-Voigt Model

I have a system where two particles $x_1$ and $x_2$ in one dimension are connected by a spring and a dash in parallel. This is analogous to the Kelvin-Voigt model for viscoelastic materials. The two ...
1 vote
21 views

### Relation between power dissipation and imag part of susceptibility [duplicate]

I am trying to understand the following relation between power dissipation and the imaginary part of the susceptibility, from Sethna's Statistical Mechanics textbook. Why does the integral equal the ...
20 views

### Conditions for the existence of a steady state in time-driven system

Consider an open quantum system given by the Hamiltonian $$H = H_B + H_S(t) + H_{SB}$$ with $B$ denoting the noninteracting bath, $H_S(t)$ the time-dependent noninteracting system and $H_{SB}$ is a ...
1 vote
62 views

### Pushing a Hamiltonian part into dissipative part in Lindbladian

Suppose we have the following Lindbladian: $$\mathcal{L}(\rho) = -\frac{i}{\hbar}[H, \rho] + \sum_\alpha L_\alpha \rho L_\alpha^\dagger - \frac{1}{2}\{L_\alpha^\dagger L_\alpha, \rho \}.$$ Suppose we ...
111 views

### How does energy conversions happen in the circuit?

Let's imagine that we have battery connected to wire and the only component in circuit is light bulb and let's say we got 5V in battery. I'm looking for the intuitive explanation and not with the ...
1 vote
57 views

34 views

### Damped oscillation experiment - damped harmonic motion

Does anyone know of any easy experiments to do that involves damped spring harmonic motion? Preferably an experiment in which I vary variable A and examine how it affects variable B. I was thinking of ...
247 views

### Why does audio signal amplitude always fall off at higher frequencies?

In the frequency spectrum of every real audio sample that I've ever seen, the amplitude of the frequency components is always higher at low frequencies, then rapidly falls off at higher frequencies. ...
1 vote
59 views

### How would you experimentally determine the damping coefficient of a system?

We have a suspended beam that we need to determine the natural frequency, and more importantly the damping, of. To avoid resonance. The geometry of the beam is a little too complex to rely on theory ...
494 views

### In theory, would amplitude keep increasing forever in an oscillating system in resonace?

Because there is a limit in experiments modelling resonance, the amplitude of oscillation will eventually reach a limit. However, in theory, if there wouldn't be any limitations in the set up of the ...
1 vote
73 views

### Power consumed by an electrical load

I saw this quote on a website recently: "A fundamental law of electric circuits is, that because current must be constant all the way around a circuit, only half the power of a generator can be ...
1 vote
62 views

### Transient power spectrum of a damped, driven simple harmonic oscillator (DDSHO)

Our prof in the class mentioned something called the transient power spectrum of a damped, driven simple harmonic oscillator (DDSHO). Assuming that we're given the drive frequency, and we're to find ...
28 views

### Why does hot water in a hot flask later cool? [duplicate]

What make hot water cool in thermos flask since it doesn’t release energy?
1 vote
122 views

### Does energy conservation law conflict with Active Noise Cancellation

Assume the picture below: From inlet port In1 and In2 we can have electromagnetic or acoustic energy entrace single sine wave with same amplitude and frequency. Assume we have aligned the waves to ...
922 views

### Will an ideal bouncing ball ever stop bouncing?

By an ideal ball I mean a bouncing point mass with the property that it loses half of the velocity (50%) after each bounce. Now according to my definition of ideal ball, it is impossible for the ball ...
81 views

### Is tidal energy an infinite source of energy?

As tidal waves are caused due to gravitational force which acts infinitely until the presence of mass (the Moon) which make me think of an infinite source of energy. So what's wrong in here?
146 views

### Why wouldn't this perpetual motion machine based on Archimede's principle work? [duplicate]

I found this today on the interwebs: Obviously this cannot work, but what bugs me is that I cannot figure out the part that would stop it and bring it to equilibrium. I suspect that it has to do ...
293 views

### Is 100% of the energy consumed by a light bulb eventually converted into heat?

I understand that any light bulb, whether incandescent or LED, transforms a part of the energy it consumes into heat and the rest into radiation (mainly visible light). Assuming a 10W LED light bulb ...
31 views

308 views

### Is a superconductor 'perfect'? i.e. does current flow forever without decaying? [duplicate]

In a (say) circular superconducting loop which has a current initially induced in it, and without any further external influences, and at a temperature above 0 K and below the transition temperature, ...
133 views

### Yet another perpetual motion machine: does this imply large selective membranes are not possible? [closed]

So I was just thinking about the buoyant force and came up with what seemed like a simple perpetual motion based on it. Obviously such things are not physically possible so I'm trying to figure out ...
1 vote
74 views

### What does it mean for $\omega$ to not be "real" in practice?

I am reading about landau damping and the author states that $\omega$ is never real (due to collisions). https://cds.cern.ch/record/1982428/files/377-404%20Herr.pdf \begin{equation} 1 + \frac{\...
105 views

### Piano on the moon

Imagine a piano on the moon. You strike a chord. Since there is no atmosphere, there is no medium for the sound to travel. so where does the sound energy go? Does it just dissipate as another form of ...