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Probability

Question
CBSEENMA9003462
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A right circular cylinder just encloses a sphere of radius r. Find

(i)     surface area of the sphere,
(ii)    curved surface area of the cylinder,
(iii)    ratio of the areas obtained in (i) and (ii).




Solution

(i)     Surface area of the sphere = 4πr2
(ii)    For cylinder Radius of the base = r
Height = 2 r Curved surface area of the cylinder = 2π(r)(2r) = 4πr2
(iii)    Ratio of the areas obtained in (i) and (ii)
equals fraction numerator Surface space area space of space the space sphere over denominator Curved space surface space area space of space the space cylinder end fraction equals fraction numerator 4 πr squared over denominator 4 πr squared end fraction equals 1 over 1 equals 1 space colon space 1

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