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Inverse Square vs Exponential

As far as I understand, in exponential equation the variable (x) is in the exponent. In a power function the variable is the base. In inverse square law, the intensity is inversely related to the ...
Narayanan 's user avatar
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Why does critical damping return to equilibrium faster than overdamping?

WLOG you can rescale x so that the initial displacement is 1 and rescale time so that $\omega _0 = 1$. For convenience you may also relabel $\gamma = 2q$ which is fine because we will check our result ...
Harvey Williams's user avatar
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Where does a body get its energy to heat up when falling from height $h$?

A body that is at some height $h$ has some potential energy due to Earth's gravitational field. When it is dropped, then it will be converted into kinetic energy. Let us say that when there is no air ...
Proscionexium's user avatar
2 votes

Where does a body get its energy to heat up when falling from height $h$?

When a body falls from height part of its energy is lost due to friction with air. Note that the temperature is only a measure of the kinetic energy of the molecules of an object. Due to the effect of ...
Alessandro Bertoli's user avatar
1 vote

Heat as a path dependent integral

The notation used for heat in thermodynamic processes is one of the poorest in Physics. A source of confusion is that the total exchanges of heat (Q) and work (W) always sum to the internal energy ...
GiorgioP-DoomsdayClockIsAt-90's user avatar
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Heat as a path dependent integral

Since all infinitesimally transported heat $\delta Q$ is also some amount of entropy $dS$ transported at some temperature $T$, that is, $\delta Q = TdS$, you can always sum (integrate) their product ...
hyportnex's user avatar
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Accelerating car under the influence of rolling friction

I've already accepted user256872's answer, but I just wanted to add some remarks to point out the flaws in my initial reasoning. Conventions about frictional forces Namely, my troubles seem to mostly ...
BlenderBender's user avatar
1 vote
Accepted

Accelerating car under the influence of rolling friction

The idea of rolling friction is fundamentally a macroscopic, experimental observation, which states that the work is $dw=\mu_R m\vec g\cdot d\vec s$. As for your questions, The dissipational energy ...
user256872's user avatar
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Direct conversion of potential energy into heat

It is a little unclear what you mean. Heat is the energy of the atoms in a substance. In an ideal gas, they bounce around randomly. Heat is their kinetic energy. In a solid, they are held in place by ...
mmesser314's user avatar
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Energy and Non-conservative forces

I understand that one cannot assign a potential energy to all points in space in the presence of a non-conservative force field due to the work done by the force being dependent on the path taken. ...
Ján Lalinský's user avatar
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Energy and Non-conservative forces

However, I have often come across this statement that energy is "irrecoverably" lost when work is being done in a non-conservative force field (look at the photo below for example). What ...
Bob D's user avatar
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1 vote

Energy and Non-conservative forces

The quote at best is a badly phrased sentence, at worst is a fundamental misunderstanding. Instead of being unrecoverable the entropy generated by friction and other irreversible processes are in fact ...
hyportnex's user avatar
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Energy and Non-conservative forces

In case of a Conservative force the work done by it is position dependent, it has no dependence on the path, so in a round trip if the system comes back to its initial configuration the work done by ...
SURYABARTA SAHA's user avatar
2 votes

Energy and Non-conservative forces

Work is lost at a macroscopic level, but nothing is lost if you look at the microscopic level. "Lost work" at the macroscopic level correspond to an increase of internal energy (and often ...
basics's user avatar
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Where does the energy go in inelastic collisions?

An example in a very different context is in atomic and molecular collisions with surfaces. If I shoot an atom at a surface with some kinetic energy $T_i$ and it bounces off the surface with a kinetic ...
intraband's user avatar

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