The capacity of a closed cylindrical -Maths 9th

The capacity of a closed cylindrical -Maths 9th
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Height of the cylindrical vessel (h) = 1 m Capacity of the cylindrical vessel = 15.4 L = 15.4/1000 m 3 = 0.0154 m3 Let 'r' m be the radius of the base of the cylindrical vessel Volume of the cylindrical vessel = πr2h ⇒  πr2h  = 0.0154 ⇒ 22/7 x r2 x 1 = 0.0154 ⇒  r2 = (0.0154 x 7)/22 =  0.0049    ⇒ r = 0.07 m Metal sheet needed to make the cylindrical vessel = Total surface area of the cylindrical vessel  = 2 π/(r + h) = 2 x 22/7 x 0.07(0.07 + 1) m2 = 1/7 x 44 x 0.07 x 1.07 m2  = 0.4708 m2
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Last Answer : Let h be the height and r be the radius of a cylindrical tank. Height of cylindrical tank, h = 1m Radius = half of diameter = (140/2) cm = 70cm = 0.7m Area of sheet required = Total surface are of tank = 2πr( ... [2 (22/7) 0.7(0.7+1)] = 7.48 Therefore, 7.48 square meters of the sheet are required.

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