In Fig., a right circular cylinder just encloses a sphere of radius r. Find -Maths 9th

In Fig., a right circular cylinder just encloses a sphere of radius r. Find -Maths 9th
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(i) Surface areas S1 of the sphere = 4 πr2 (ii) We have Radius of the cylinder = r  Height of the cylinder = h = 2r ∴  Curved surface area S2 of the cylinder                                                                                                        2 πrh  = 2 πr x 2r = 4 πr2 (iii) S1/S2  = 4 πr2/4 πr2 = 1/1 ∴  S1 : S2 = 1 : 1
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