Novice question

[DevilSolution]

Does there exist any physical equation where time is not a variable, this obviously includes any derivatives.

 

Also I'll tighten the parameters a little such that anything involving EM waves are a function of time (such that 1 cycle from any wave is the shortest unit of moment)

 

Secondly, quantum mechanics is disqualified, mainly due to the fact i have little comprehension of it, However feel free to write an QM equation that also doesnt have a derivative in time.

 

Regards.

 

 

As a side topic, i just realised there are plenty of equations regarding force and energy.

 

Force refers to motion which atleast has a term of time.

Energy i suppose is unique however disregarding potential energy, Any transformation of energy must have a time element.

 

I think there will be definitions? but no relationships.

 

the definition of a watt = amps * volts, which obviously has no T in there but both volts and amps do, they are derived using time.

Edited November 16, 2015 by DevilSolution

[studiot]

I suppose with all your restrictions it boils down to

 

What can I do if I drop T from MLT dimensions.

 

So, how about the formula for the focal length of a lens.

 

(There are plenty of other optical formulae in that stable)

 

Or the formulae for the coordinates of a centroid. The ration of two triple integrals should be mathematical enough for you.

[DevilSolution]

I suppose with all your restrictions it boils down to

 

What can I do if I drop T from MLT dimensions.

 

So, how about the formula for the focal length of a lens.

 

(There are plenty of other optical formulae in that stable)

 

Or the formulae for the coordinates of a centroid. The ration of two triple integrals should be mathematical enough for you.

 

 

The second example is purely mathematical, well i mean you'd find it in a maths book not a physics book...although it may be related.

 

The first pertains to a property of a physical entity, which is fair enough, i suppose that would be a category thats stands outside of time.

 

So then all physics other than equations regarding physical properties of an entity are based on time? It is the relation of change between entities?

Edited November 16, 2015 by DevilSolution

[swansont]

In any steady-state solution, time is not a variable. The total energy of an isolated system, for example.

 

There are work-related equations where time is removed because the quantities involved are position-dependent. v^2= 2 a(dot)s, for example. Equations involving KE and PE

[studiot]

 

 

The second example is purely mathematical, well i mean you'd find it in a maths book not a physics book...although it may be related.

 

The first pertains to a property of a physical entity, which is fair enough, i suppose that would be a category thats stands outside of time.

 

So then all physics other than equations regarding physical properties of an entity are based on time? It is the relation of change between entities?

 

I don't see that the centroid (or centre of gravity) is purely mathematical, simple versions were included in my O level Physics, not in my O level Mathematics.

It was in both A level (applied) Maths and Physics.

It did not appear in maths degree, I do not have a physics one to compare, but it was heavily used in my engineering degree, where it was assumed to be known about.

[math]\bar x = \frac{{\smallint \smallint \smallint \rho xdxdydz}}{{\smallint \smallint \smallint \rho dxdydz}}[/math]

 

But yes the centroid is a property of an object, but not a material property. And it is time independent.

Density is a material property.And it is time independent.

[math]\rho = \frac{m}{V}[/math]

 

Another object property is the metaheight used in floating bodies such as ships and icebergs.

[math]h = \frac{m}{M}d\cot (\theta )[/math]

 

I know I said the focal length of a lens but I was really referring to the lens equation, which is time independent.

This is more than just a property, is is a relationship between three physical quantites.

[math]\frac{1}{u} + \frac{1}{v} = \frac{1}{f}[/math]

 

Charle's law is time independent, and enjoys the status of a Law of Thermodynamics in Physics.

 

[math]\frac{{{V_1}}}{{{V_2}}} = \frac{{{T_1}}}{{{T_2}}}[/math]

 

I don't know if you would include balanced (stoichiometric) chemical reaction equations but they are time independent but refer to change.

[math]C + {O_2} \to C{O_2}[/math]

 

So I think the examples are there if you care to look.

 

Edited November 17, 2015 by studiot

[MigL]

Seems simple enough.

The equations of any model which describe evolution in time of the system, by necessity, involve the time variable.