Is the book wrong again for this e field problem?

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The discussion centers on calculating the total charge of a nonconducting spherical shell with a uniform volume charge density. The user derived the total charge as Q = p(4/3)π(R2^3 - R1^3), while the book suggests Q = p(4/3)π(r^3 - R1^3). The discrepancy arises because the book's formula may refer to the charge within a radius r, applicable for electric field calculations using Gauss' law. The user is encouraged to verify the book's context regarding the radius r. Overall, the user's calculation for the total charge on the shell is confirmed as correct.
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Homework Statement



A nonconducting SPHERICAL SHELL of inner radius R1 and outer radius R2 has a uniform volume charge density p. Find the total charge on the shell

Homework Equations


Q=pV=p(4/3)*pi*(R2^3-R1^3) << That's what I got
the book had Q=pV=p(4/3)*pi*(r^3-R1^3) <<how can that be correct if you're finding the total charge the shell, not from R1 to r?
 
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Your answer is right, but are you sure that you are quoting the book correctly? The book could be referring to the charge contained within a radius r, such that R1<r<R2 (which can be applied to find the electric field by Gauss' law)
 

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