I don't understand this problem -- Surface area of a section of a solid sphere

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samy4408
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Homework Statement
...
Relevant Equations
...
Sorry i don't understand English very well , if someone want to explain to me this problem?
2022-03-04 18_34_35-Window.png
 
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What part is giving you difficulty?
Try your best to explain what you think it's asking for. We'll see of we can set you straight.
 
samy4408 said:
Homework Statement:: ...
Relevant Equations:: ...

Sorry i don't understand English very well , if someone want to explain to me this problem?
View attachment 297876
Ordinarily I would delete a post like this, as there is no work shown, but today is your lucky day.
Do you know a formula for the surface area of a sphere whose radius is given?
Can you determine what fraction of a sphere is shown in the picture?
 
The problem is asking you to calculate the surface of a sphere that has been cut as shown.
Can you see it tridimensional in your head?
 
Mark44 said:
Ordinarily I would delete a post like this, as there is no work shown, but today is your lucky day.
Do you know a formula for the surface area of a sphere whose radius is given?
Can you determine what fraction of a sphere is shown in the picture?
I do know the formula for the surface area of a sphere , the problem is what they are asking for ,
is it the surface of the sphere that is shown ? is it 1/8 of the total surface of the sphere ?
 
phinds said:
yes
No. You also have to add on the new faces from the cut.
 
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caz said:
No. You have to add on the new faces from the cut.
Ah. You are right of course. I missed that they want ALL of the surface area. Still a trivial problem.
 
samy4408 said:
So it is 2*pi
That's just the surface area of the part of the sphere. The problem is asking for the area of the partial sphere surface, plus the three other sides.
 
caz said:
No. You also have to add on the new faces from the cut.
It says a "solid sphere", so this is correct, IMO. If it was just a spherical surface that was cut, it would be different.
 
Well boo. You guys moved on while I was busy rendering a visual aid.

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