Centroids Simplifying by symmetry

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SpartanG345
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If you have a 3d shape how do you simplify the problem using symmetry.

eg with a sphere is symmetric along any axis therefore the centroid must be in the middle of it

eg2 A cone sitting on the xy plane, where the pointy bit is points up the z axis.
-nb it is sitting on point (0,0,0) where the circular crossection lines on the xy plane at z = 0
with a centre at (0,0)

you can intuitively see that the centroid must have an x coordinate of 0 and a y coordinate of 0 and there some random number for the z coordinate.

where my understanding of symmetry is if a shape can be rotated about an axis and look the same then it is symmetric... this many not the be official definition though

it seems to me that if a shape is symmetric across an axis, only a distance along that axis will need to be calculated to get the centroid. Is this right?
 
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Hi SpartanG345! :wink:
SpartanG345 said:
… where my understanding of symmetry is if a shape can be rotated about an axis and look the same then it is symmetric... this many not the be official definition though

It's good enough! :smile:
it seems to me that if a shape is symmetric across an axis, only a distance along that axis will need to be calculated to get the centroid. Is this right?

("symmetric about an axis")

Yup, that's completely right! :biggrin: