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प्रश्न
The diameter of a garden roller is 1.4 m and it 2 m long. Find the maximum area covered by its 50 revolutions?
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उत्तर
Diameter of the roller = 1.4 m
Radius (r) = `1.4/2` = 0.7 m
and length (h) = 2m
Curved surface area = 2πrh = 2 x `22/7` x 0.7 x 2 cm2 = 8.8 m2
Area covered in 50 complete revolutions = 8.8 x 50 m2 = 440 m2
Area of the playground = 440 m2
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