What's is dv for a finite cylinder?

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For a finite cylinder, the differential volume element is indeed expressed as dV=π*L*r*dr, while for an infinite cylinder, it is dV=2*π*r*L*dr. The discussion emphasizes that both formulas are valid, but the infinite cylinder's formula assumes a constant volume per unit length, which can complicate calculations if the length (L) is unknown. The user is encouraged to refer to external resources for a deeper understanding of the geometric principles involved. Overall, the conversation clarifies the application of volume formulas for different types of cylinders.
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For an infinite cylinder dV=2*pi*r*L*dr
Would dv=pi*L*r*dr for a finite cylinder?
 
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charlies1902 said:
For an infinite cylinder dV=2*pi*r*L*dr
Explain this in words, to show that you understand it and how it arises.
 
Yes, this definitely still holds;
I could also refer you here, for the proof:http://en.wikipedia.org/wiki/Cylinder_(geometry)#Volume"
Beware that an infinite cylinder carries, A volume per unit length, or, L is unknown...
Both formulae are correct and useable...
 
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