- #1
danago
Gold Member
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A cylinder is placed into a right cone which has a radius of 1m and a height of 2m. Find the maximum volume of the cylinder.
I think i am able to do it, but I am not 100% sure if I am correct. I first used similar triangles to write the radius of the cone at any height from its apex. i came up with h=2r.
Now, if i let the radius of the cylinder be R, then the height that it rests at is 2R. Since the cone is 2m high, the height of the cylinder will be 2-2R.
The volume is given by [tex]V = \pi R^2 (2 - 2R)[/tex], which i used calculus to maximize and came up with R=2/3, therefore V=~0.93. Does that look right?
Thanks in advance,
Dan.
I think i am able to do it, but I am not 100% sure if I am correct. I first used similar triangles to write the radius of the cone at any height from its apex. i came up with h=2r.
Now, if i let the radius of the cylinder be R, then the height that it rests at is 2R. Since the cone is 2m high, the height of the cylinder will be 2-2R.
The volume is given by [tex]V = \pi R^2 (2 - 2R)[/tex], which i used calculus to maximize and came up with R=2/3, therefore V=~0.93. Does that look right?
Thanks in advance,
Dan.