2006-12-19 04:31:00 · 11 answers · asked by Santhanakrishnan v 1 in Science & Mathematics ➔ Geography
The surface area of a sphere of radius 'r' is given by:
surface area = 4pr2
NOTE: The value of p can never be known exactly, so surface areas of spheres cannot be calculated exactly. Common approximations for p are: 3.14, and 22/7.
Example 1 if 'r' = 5 for a given sphere, and p = 3.14, then the surface area of the sphere is:
surface area = 4pr2
= 4 × 3.14 × 52
= 314
to understand clearly visit http://www.teacherschoice.com.au/Maths_Library/Area%20and%20SA/area_2.htm
2006-12-19 04:59:03 · answer #1 · answered by Anonymous · 4⤊ 2⤋
The surface area of a sphere of radius 'r' is given by:
Surface area = 4*pi*r^2
Sphere Surface Area=4 • pi • r²=pi • d²
NOTE: The value of pi can never be known exactly, so surface areas of spheres cannot be calculated exactly. Common approximations for p are: 3.14, and 22/7.
Example: if 'r' = 5 for a given sphere, and pi = 3.14, then the surface area of the sphere is:
surface area = 4*pi*r^2
= 4 × 3.14 × 5^2
= 4 × 3.14 × 25
= 314 unit^2
For more details other than surface area of sphere, click:
http://www.teacherschoice.com.au/Maths_Library/Area%20and%20SA/area_2.htm
http://mathforum.org/library/drmath/view/55135.html
(The surface area of a sphere is equal to 4*pi*r^2. Analogous to the unit circle is the unit sphere. Similarly, just as there are 2*pi radians of angle in one revolution, there are 4*pi steradians of solid angle in all directions.)
2006-12-19 06:49:48 · answer #2 · answered by namrata00nimisha00 4 · 0⤊ 1⤋
So far all answers are correct:
S = 4*pi*r^2
If you mean surface area of a sphere.
2006-12-19 22:14:54 · answer #3 · answered by minootoo 7 · 0⤊ 0⤋
Dont hear to the others. the main appropriate formula for the floor portion of a sphere is 4*pi*r*r. (4 pi r squared). 4/3 pi r^3 is the formula for the quantity of the sector. a stable thank you to tell that the 4/3 pi r^3 formula is incorrect is to observe that volumes generally incorporate cubes whilst factors generally incorporate squares....
2016-12-30 15:53:39 · answer #4 · answered by Anonymous · 0⤊ 0⤋
The surface area of a sphere is A=4*pi*r^2 where r is the radius of the sphere. The *volume* is (4/3)*pi*r^3.
2006-12-19 04:41:51 · answer #5 · answered by Outdoorsman 3 · 1⤊ 4⤋
4 X Pi X r2
2006-12-19 19:46:23 · answer #6 · answered by K.Easwaran Venkatesh 1 · 0⤊ 0⤋
The formula for the surface area is 4*pi*r^2.
The formula for the volume is 4/3*pi*r^3.
(where 'r' is the radius)
2006-12-19 04:34:13 · answer #7 · answered by Bugmän 4 · 1⤊ 4⤋
there are 2 areas , one LSA another TSA.
But for sphere both are
4. pi.r*r
2006-12-20 17:39:11 · answer #8 · answered by SAMS 2 · 0⤊ 0⤋
you mean surface area.
if radius is R cm
surface area of sphere
=4*Pi*R^2 cm^2[Pi=22/7]
2006-12-19 04:35:53 · answer #9 · answered by openpsychy 6 · 1⤊ 5⤋
S = 4*pi*r^2
2006-12-19 04:33:32 · answer #10 · answered by AresIV 4 · 0⤊ 5⤋