could u tell me the proof for surface area of a sphere.?

Question

i would like to get an answer in ten minutes. no bluffing.

Answer 1

http://mathforum.org/paths/measurement/aos.html

Answer 2

Stand at sea point and watch a tall deliver sail removed from you. It does not merely get smaller and smaller, first the hull disappears, then the superstructure, then the decrease sails, then the top sails and finally the masthead, because of the fact that's disappearing over the curve of the Earth. in case you recognize the top of your eye, the top of the masthead and the linked fee of the vessel (which will desire to be consistent) you have got a stab at calculating the curvature, however i'm no longer likely to attempt to describe the math right here. Or degree the angular top of the solar at midday from you very own area and from 200 miles north or south of your place. this will additionally help come across the curvature. Or Watch the eclipse of the moon from diverse places. The Earth's shadow on the moon is often around. purely a sphere can forged a around shadow in any course.

Answer 3

Surface Area of a Sphere = 4 pi r squared

pi = 3.14
r = radius

So, 4 X 3.14 X Radius Squared

http://www.math.com/tables/geometry/surfareas.htm

Answer 4

well, the circle equation is z^2+y^2=r^2.
if we rotate it about the x-axis, we'll get a sphere.
through the surface of revolution and the volume formulas, the volume and surface of revolution can be found with the help of integral calculus.
you can also find it through differentiation. the equation of sphere is
x^2+y^2+z^2=r^2

Answer 5

Easiest way is to do the derivative of the volume. And the volume can be calculated by taking the integral of x and y of the equation for the sphere. x^2 + y^2 + z^2 = r^2

I actually don't know of another way, but I'll think about it.

Answer 6

area of circle = pi*(r^2)
volume of sphere = 4*pi*(r^3)
combining these two and reducing it further we get surface area of sphere = 4*pi*(r^2)
cannot explain in detail as you dont have time

Answer 7

if a circle is rotated you get the surface of a sphere
limit 0 to 2r S2pir=2pir^2/2
pi(4r^2-0)=4pir^2

Answer 8

I am sorry I am late. the 10 minutes limit is over but I have the proof.

Answer 9

area of surface of sphere = square of diameter multiplied by 3.146

Answer 10

get proof of volume of sphere
then differentiate it

Answer 11

Spheres or balls it's all the same to me.