Attached picture below.
Problem: Calcuate center of mass of the slender rod.
Since the density varies, I did: With , because I guess the area is the same throughout the rod.
Thx for your help!
A doesn't affect the result because it is assumed to be constant.
A two-dimensional figure is a as good as a one-dimensional as long as one dimension remains unchanged.
For example, if we are dealing with all rectangles with the same same, then we have to consider only their relative length..hence problem comes in the realm of one-dimension.