Unravelling Surface Area of a Dome

DaveC426913
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Trying to figure out the answer to another thread.

What is formula for the surface area of a dome?

Googling got me 2\pi r h (where h is the height of the dome above its slice through the sphere). Is that right?

Ultimately, I'm trying to figure out how the area changes as a function of the slice through the sphere. i.e.:

When the slice goes through the centre of the sphere, the area is X (in fact, exactly half of the sphere's area).

OK. Now, if I move the slice out to 1/2 r, what does that do to the area of the dome? Does the area halve? or quarter?
 
Mathematics news on Phys.org
I advise u draw a picture.Explain the geometry of the drawing.Which is the sphere,which is the paraboloid,is it a revolution paraboloid,are they coaxial,what is "h",what is "r",or simply give the link to the webpage where u got that result.

If you're asking for help,at least do it in a proper way.

Daniel.
 
Guess I didn't get the memo on "the proper way".


(Don't know why this gpt posted twice...)
 
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