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प्रश्न
The height of a circular cylinder is 20 cm and the diameter of its base is 14 cm. Find:
(i) the volume
(ii) the total surface area.
उत्तर
Height of cylinder (h) = 20 cm
and diameter of its base (d)= 14 cm
and radius of its base (r)= `14/2` = 7 cm
(i) Volume = πr2h
= `22/7 xx 7 xx 7 xx 20` cm3 = 3080 cm3
(ii) Total surface area = 2πr(h + r)
= `2 xx 22/7 xx 7 (20 + 7)` cm2 = 44 x 27 = 1188 cm2
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