Velocity with respect to acceleration

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Discussion Overview

The discussion revolves around the differentiation of functions with respect to acceleration, particularly in the context of velocity and energy. Participants explore the mathematical relationships and implications of these derivatives, focusing on theoretical aspects rather than practical applications.

Discussion Character

  • Mathematical reasoning
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions the feasibility of differentiating a function with respect to acceleration when the function is expressed in terms of velocity.
  • Another participant suggests that if the acceleration/time relationship is invertible, the derivative of velocity with respect to acceleration can be expressed as a fraction of acceleration and its rate of change.
  • A participant expresses uncertainty about their mathematical skills and seeks to understand the relationship between energy and acceleration, presenting an expression for dE/da.
  • There is a reiteration of the need to use the chain rule for differentiation, with a focus on expressing velocity in terms of acceleration before proceeding.
  • One participant emphasizes that since velocity is the only variable in the equation, it must be expressed in terms of acceleration to differentiate correctly.
  • Another participant confirms the use of the chain rule in the context of differentiating energy with respect to acceleration.

Areas of Agreement / Disagreement

Participants express differing views on the approach to differentiating with respect to acceleration, particularly regarding the necessity of expressing velocity in terms of acceleration. There is no consensus on the best method to proceed with the differentiation.

Contextual Notes

Participants acknowledge limitations in their mathematical skills and the complexity of the relationships being discussed, which may affect their ability to resolve the differentiation accurately.

Zman
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Is it possible to differentiate a function with respect to acceleration where the function is expressed in terms of velocity?

[tex]\frac{dy}{da} = \frac{d}{da}{\frac{1}{\sqrt{1 - v^2/c^2}}}[/tex]
 
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Well, if say the acceleration/time-relationship is invertible, so that time may be regarded as a function of the acceleration, we would have:
[tex]\frac{dv}{da}=\frac{dv}{dt}\frac{dt}{da}=a\frac{dt}{da}=\frac{a}{\frac{da}{dt}}[/tex]

Thus, the derivative of velocity wrt. to acceleration is the fraction between the acceleration itself and its rate of change.
 
Thanks for your reply.
I tried to keep my question simple but I think that that was a mistake. My maths is extremely rusty and I definitely feel uncomfortable with it.

The situation that I am dealing with is the relationship between the energy of a body and its acceleration.

I want to determine the relationship dE/da (E is energy, a is acceleration)
I have arrived at the expression;
[tex]\frac{dE}{da} = \frac{d}{da}{mc^2\frac{1}{\sqrt{1 - v^2/c^2}}}[/tex]

and I am not sure how to proceed from this point.
 
Zman said:
Thanks for your reply.
I tried to keep my question simple but I think that that was a mistake. My maths is extremely rusty and I definitely feel uncomfortable with it.

The situation that I am dealing with is the relationship between the energy of a body and its acceleration.

I want to determine the relationship dE/da (E is energy, a is acceleration)
I have arrived at the expression;
[tex]\frac{dE}{da} = \frac{d}{da}{mc^2\frac{1}{\sqrt{1 - v^2/c^2}}}[/tex]

and I am not sure how to proceed from this point.

[tex]mc^2(1- v^2/c^2)^{-1/2}[/tex]
Now use the chain rule.
 
The velocity v is the only variable in the equation. Surely I need to express v in terms of acceleration ‘a’ before I can differentiate the expression using the chain rule?

If I was resolving dE/dv, I believe that I could go ahead and differentiate the expression using the chain rule but I am trying to resolve dE/da.
 
dE/da = dE/dv*dv/da

aka the chain rule. Go for it
 

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