If surface area of a sphere is 784πcm2 .Find its radius.

1.	If surface area of a sphere is 784πcm2 .Find its radius.
Answer» ong>Given: Surface area of SPHERE = 784 π cm² ⠀⠀⠀ To FIND: RADIUS of sphere? ⠀━━━━━━━━━━━━━━━━━━━━━━━ Sphere is a BALL shape where the surface is the same distance from the center at all points. ⠀⠀⠀ ⌬ Let radius of sphere be r cm. ⠀⠀⠀ We know that, ⠀⠀⠀ $\star\;{\boxed{\sf{\purple{TSA_{\;(sphere)} = 4 \pi r^2}}}}\\ \\$ Now, Putting values, ⠀⠀⠀ $:\implies\sf 4 \cancel{\pi} r^2 = 784 \cancel{ \pi}\\ \\$ $:\implies\sf 4 \times r^2 = 784\\ \\$ $:\implies\sf r^2 = 784 \times \dfrac{1}{4}\\ \\$ $:\implies\sf r^2 = 196\\ \\$ $:\implies\sf \sqrt{r^2} = \sqrt{196}\\ \\$ $:\implies{\boxed{\sf{\pink{r = 14\;cm}}}}\;\bigstar\\ \\$ $\therefore\;{\underline{\sf{Hence,\;Radius\;of\;sphere\;is\; \bf{14\;cm}.}}}$ ⠀⠀⠀━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ $\qquad\qquad\boxed{\underline{\underline{\bigstar \: \bf\:More\:to\:know\:\bigstar}}} \\ \\$ TSA of hemisphere = 3πr² CSA of hemisphere = 2πr² Volume of sphere = 4/3 πr³ Volume of hemisphere = 2/3 πr³

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ong>Given: