(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The soot produced by a garbage incinerator spreads out in a circular pattern. The depth H(r) in millimeters, of the soot deposited each month at distance r kilometers from the incinerator is given by H(r) = 0.115e^(-2r)

Write the definite integral for the amount of soot deposited per month in a 5 kilometer radius.

2. Relevant equations

3. The attempt at a solution

Looks easy, but something is confusing me.

I integrate from 0 to 5 kilometers and multiply H(r) by 2pir, but since these functions give out different units, one in millimeters and one in kilometers, how can I just straight multiply? I divided H(r) by 10e^6 to put the millimeters into kilometers, but the book doesn't do that. The book just multiplies the two functions and integrates from 0 to 5.

Why is no unit conversion nessesary?

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# Homework Help: Volume Integral homework

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