Q8 of 32 Page 255

A wooden article was made by scooping out a hemisphere from each end of a solid cylinder, as shown in the figure. If the height of the cylinder is 10 cm. and its radius of the base is of 3.5 cm, find the total surface area of the article.

Given that, radius(r) of base is 3.5 cm and height(h) of cylinder is 10 cm.

⇒ the total surface area of the article = surface area of cylinder +


2(Surface area of hemisphere)


= 2πrh + 2(2πr2)


= 2πr(h + 2r)




= 374 cm2


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