- #1
Chenkel
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- TL;DR Summary
- I'm trying to understand a strange integral in Chris McMullen's book "Essential Calculus-based PHYSICS"
Hello everyone!
I've been reading Mr. McMullen's book and took some curiosity in an equation on the cover art, it is as follows:$$y_{cm} = \frac \rho m \int_{r=0}^R\int_{\theta=0}^\pi (r\sin \theta)rdrd\theta$$I'm trying to understand what it means, firstly the limits of integration for the inner integral are theta, and we're integrating with respect to r; then on the outer integral, the limits of integration are r, and the variable we're integrating with respect to is theta. I'm used to the variable for the limits of integration matching the variable we're integrating with respect to, does this equation make sense to anyone? Let me know what you think, thank you!
I've been reading Mr. McMullen's book and took some curiosity in an equation on the cover art, it is as follows:$$y_{cm} = \frac \rho m \int_{r=0}^R\int_{\theta=0}^\pi (r\sin \theta)rdrd\theta$$I'm trying to understand what it means, firstly the limits of integration for the inner integral are theta, and we're integrating with respect to r; then on the outer integral, the limits of integration are r, and the variable we're integrating with respect to is theta. I'm used to the variable for the limits of integration matching the variable we're integrating with respect to, does this equation make sense to anyone? Let me know what you think, thank you!