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#1 2015-05-12 03:43:17
- shyclaw
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- From: Dagoba
- Registered: 2015-03-23
- Posts: 67
Finding The Surface Area Of A Cylinder
Could someone tell me what this formula for finding surface area means??
A = πr²
Thanks For the help!!!
-Shyclaw ;D
"“A Jedi uses the Force for knowledge and defense, never for attack.”
-Yoda
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#2 2015-05-12 03:48:35
Re: Finding The Surface Area Of A Cylinder
This formula gives you the area of a *circle* whose radius is r
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#3 2015-05-12 03:54:02
- shyclaw
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- From: Dagoba
- Registered: 2015-03-23
- Posts: 67
Re: Finding The Surface Area Of A Cylinder
This formula gives you the area of a *circle* whose radius is r
Thank you! ☺
Shyclaw
"“A Jedi uses the Force for knowledge and defense, never for attack.”
-Yoda
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#4 2015-05-12 04:16:14
Re: Finding The Surface Area Of A Cylinder
That is not the surface area of a cylinder
'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.
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#5 2015-05-12 06:00:36
- shyclaw
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- From: Dagoba
- Registered: 2015-03-23
- Posts: 67
Re: Finding The Surface Area Of A Cylinder
That is not the surface area of a cylinder
?
"“A Jedi uses the Force for knowledge and defense, never for attack.”
-Yoda
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#6 2015-05-12 07:48:30
- Bob
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- Registered: 2010-06-20
- Posts: 10,627
Re: Finding The Surface Area Of A Cylinder
If you take a cylinder and "unroll" it you get a rectangle. The width is equal to the circumference of the top ie. 2 x pi x radius and the height is the height of the cylinder
Bob
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You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
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#7 2015-05-15 11:07:38
- math9maniac
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- From: Tema
- Registered: 2015-03-30
- Posts: 443
Re: Finding The Surface Area Of A Cylinder
Consider a cylinder with base radius, r and height, h.
The curved surface area of a cylinder = 2(pi)rh
The total surface area of a closed or solid cylinder = 2(pi)r^2 + 2(pi)rh = 2(pi)r (r + h)
This includes the area of the two circular ends.
The total surface area of a hollow cylinder with one end open = pi(r^2) + 2(pi)rh = pi.r(r + 2h)
The total surface area of a hollow cylinder with both ends open = 2(pi)rh
The volume of a cylinder = pi.r^2h
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