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प्रश्न
The volume of a hemisphere is 2425`1/2cm^3`cm. Find its curved surface area?
उत्तर
Given that volume of a hemisphere`=2424(1)/2cm^3`
Volume of a hemisphere`=2/3pir^3`
⇒ `2/3pir^3=2425(1)/2`
⇒`2/3pir^3=4841/2`
⇒ `r^3=(4851xx3)/(2xx2xxpi)`
⇒ `r^3=(4851xx3)/(4pi)`
r3
r = 10.50cm
∴ Radius of hemisphere = 10.5cm
Curved surface area of hemisphere = 2πr2
= 2π(10.5)2
=692.72
⇒693cm2
∴curved surface area off hemisphere = 693cm2
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