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प्रश्न
Radius of base of a cylinder is 20 cm and its height is 13 cm, find its curved surface area and total surface area. (π = 3.14)
उत्तर
Radius of the cylinder, r = 20 cm
Height of the cylinder, h = 13 cm
∴ Curved surface area of the cylinder = 2πrh
= 2 × 3.14 × 20 × 13
= 1632.80 cm2
Also,
Total surface area of the cylinder = 2πr (r + h)
= 2 × 3.14 × 20 × (20 + 13)
= 2 × 3.14 × 20 × 33
= 4144.80 cm2
Thus, the curved surface area and the total surface area of the cylinder is 1632.80 cm2 and 4144.80 cm2, respectively.
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