Question

A roller of dia. 14 cm and length 7 cm is rolled along a flat ground. Calculate the area covered when the roller makes 25 revolutions

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Answer 1

Given that .

Diameter = 14 cm

length = 7 cm

Radius = Diameter/2

Radius = 14/2 = 7cm

To find area rolled in 1 revolution we should find CSA of a cylinder.

$csa \: \: = 2\pi \: rh$

CSA = 2 ×3.14 ×7 ×7

CSA = 307.72 cm ^2

Area covered In 25 revolution = 307.72×25 = 7693 cm^2

Hope it helps ❤