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प्रश्न
A solid metal sphere of 6 cm diameter is melted and a circular sheet of thickness 1 cm is prepared. Determine the diameter of the sheet.
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उत्तर
Diameter of sphere = 6 cm
Therefore,
Radius = 3 cm.
Therefore,
Surface area of sphere
`=4pir^2`
`=4 xx pi xx (3)^2`
` = 36pi cm^2`
Area of the circular sheet `=pir^2`
Therefore,
Surface area of sphere = area of the circular sheet
`pir^2 = 36pi`
`r = 6cm`
Therefore,
Diameter of the sheet = 2 × 6 = 12 cm
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