What is the charge on a circular disc with a varying charge density?

AI Thread Summary
The discussion focuses on calculating the total charge on a circular disc with a varying charge density defined by ρs = ρs0 (e^−ρ) sin² φ C/m². Participants clarify the limits of integration, confirming they should be from 0 to a for ρ and 0 to 2π for φ. There is a concern regarding the integration of ρ due to its variability, but it is noted that the integral can still be performed. The integral setup is confirmed as Q = ∫∫ρs0 (e^−ρ) sin²(φ) dφdρ, and a reference to Wolfram Alpha is provided for assistance with the integration. The discussion concludes with an acknowledgment that the integral is feasible despite the complexity introduced by the sin² term.
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Homework Statement


Find the total charge on a circular disc of radius ρ = a if the charge density is given by
ρs = ρs0 (e^−ρ) sin2 φ C/m2 where ρs0 is a constant.
Are the two limits of integration from 0 -> a for ρ and 0->2∏ for φ? In the example given in the notes, ρ varies, instead of being a constant value. Does this mean that I cannot integrate ρ in this problem?

Homework Equations



Q = ∫ρdS

The Attempt at a Solution



Q = ∫∫ρs0 (e^−ρ) sin^2 (φ) dφdρ...
 
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With the sin term it looks like there is as much positive as negative?

Edit, now I see the sin^2

Your integral looks doable.
 
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