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CBSE Class 9 Answered

The radius of a spherical balloon increases from 7 cm to 14 cm as air is being pumped into it. Find the ratio of surface areas of the balloon in two cases.
Asked by Topperlearning User | 04 Jun, 2014, 01:23: PM
answered-by-expert Expert Answer

Radius of the spherical balloon = r1 = 7 cm

Surface area S1 of the balloon = 4

= 4(7)2

Radius of the spherical balloon when air is pumped into it = r2­

= 14 cm

Surface area S2 of the balloon =

= 4(14)2

Answered by | 04 Jun, 2014, 03:23: PM

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