Q5 of 48 Page 261

A solid is composed of a cylinder with hemispherical ends on both the sides. The radius and the height of the cylinder are 20 cm and 35 cm respectively. Find the total surface area of the solid.

Given.


A Solid is made by mounting 2 hemisphere on cylinder


The radius of the hemisphere is 20 cm.


The total height of the cylinder is 35 cm


Formula used/Theory.


Curve surface area of Cylinder = 2πrh


Curve surface area of Hemisphere = 2πr2


⇒ As we put 2 hemisphere on both sides of Cylinder


∴ Area of Solid is sum of CSA of both hemisphere and of cylinder


Area of Solid = CSA of cylinder + 2 × CSA of Hemisphere


= 2πrh + 2 × (2πr2)


= 2πr[h + 2r]


Area of solid




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