What units will the partial derivative of an angular equation give?

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Homework Help Overview

The discussion revolves around the units resulting from the partial derivative of an equation involving an angle, specifically in the context of angular equations and trigonometric functions. The original poster presents an equation that relates a variable L to constants and an angle, questioning the units of the derivative with respect to the angle.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants explore the relationship between the angle's measurement (degrees vs. radians) and the resulting units of the derivative. There is a discussion about the necessity of using partial derivatives versus ordinary derivatives in this context.

Discussion Status

Participants have offered insights regarding the expected units of the derivative, suggesting that radians are likely the standard. There is an ongoing exploration of the definitions and implications of using trigonometric functions in relation to angles.

Contextual Notes

Some participants note the lack of context for the original equation and question the appropriateness of referring to the derivative as a partial derivative given that only one variable is involved.

jeffyhow
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Homework Statement



If I have an equation that describes L in terms of some constants and an angle.

e.g. L=C1*[tex]\sqrt{(C2-Sin[angle])}[/tex]+C1*[tex]\sqrt{(C2-Cos[angle])}[/tex]

Then, if I take the partial derivative of the above wrt angle, then I would get the unit change in L for a unit change in angle.

However, if I solve the partial derivative at a specific angle, will it give me units of length/degrees or units of length/radians?

The above equation is just an example of one case for the my question.
 
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Hard to say with without a context, but probably radians. If you say the derivative of sin(x) is cos(x), then x is in radians. If your angle x is represented in degrees then the derivative of sin(x) is cos(x)*pi/180.
 
Trig functions (as opposed to values you would use to solve right triangle problems) don't necessairily have anything to do with angles. They are defined in such a way that if you are treating the variables as angles, they would have to be in radians.

I'm not sure why you are talking about "partial derivatives"- there are no partial derivatives. The only independent variable is "angle" so you only need an ordinary derivative.
 
Depends on how you integrate. If you are taking derivative of six=cosx, then x will be in radians, ie, you answer will be in lenght/rad. Oh and partial derivative, as HallsofIvy said, is not necessary, as only a single variable is involved.
 

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