Representing dv independent of time?

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The discussion explores the concept of representing velocity independently of time, particularly in the context of constant and varying acceleration. It highlights that while some equations for constant acceleration, like v = v_o + at, are time-dependent, others, such as v^2 = v_o^2 + 2as, can be formulated without direct time reliance. Various alternative formulations are proposed, including v = (ds/dt)*(dv/dv) and v = (ds/da)*j, which introduce other variables that may still depend on time. The conversation also notes that in steady fluids, velocity is defined as a function of space rather than time. Ultimately, while multiple equations can express velocity independently of time, their practical utility may vary.
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There are four basic equations for constant acceleration

v = v_o +at
v^2 = v_o^2 +2as
and so on

The first velocity is time dependent, while the second velocity relationship is time independent.

In varying acceleration, we have

v = ∫ a(t) dt

Is there any other way we can define velocity so that it is independent of time, akin to the constant acceleration above?
 
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There are infinite such ways :-)

But most of them aren't useful from practical point of view.

Still I will state one or two for you.

You can write v=ds/dt

v=(ds/dt)*(dv/dv)

[Multiplying by (dv/dv) makes no change]

V=(ds/dv)*(dv/dt)
V=(ds/dv)*a
Since a=dv/dt

On integration this yields your second equation when a is constant.


Another would be

v=(ds/dt)*(da/da)

V=(ds/da)*j

Where j is the jerk, the rate of change of acceleration.

All these equations will give you formula's independent of t. But they will contain other variables which depend on time.


Also
Remember, in steady fluids we define the velocity as a function of space and not time.
Even that picture may help you :-)
 
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