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प्रश्न
Find the volume of the hollow sphere whose inner diameter is 8 cm and the thickness of the material of which it is made is 1 cm .
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उत्तर
Inner diameter = 8 cm
Inner radius = r = 4 cm
Outer radius = R = 4cm + 1cm thick material = 5 cm
Volume of hemisphere = `2/3pir^3`
Required Volume = `4/3pi(R^3 - r^3)`
= `4/3 xx 22/7 xx (5^3 - 4^3)`
= `4/3 xx 22/7 xx 61`
= 255.6 cm3
Required volume= 255.6 cm3
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