Question

If diameter of a road roller is 0.9 m and its length is 1.4 m, how much area of a field will be pressed in its 500 rotations ?

Answer 1

Length of the road roller, h = 1.4 m
Radius of the road roller, r = `0.9/2` = 0.45 m
Now, 
Area of the field pressed in one rotation = Curved surface area of the road roller
= 2πrh
= 2 x `22/7` x 0.45 x 1.4 
= 3.96 m²

∴ Area of the field pressed in 500 rotations = 500 × Area of the field pressed in one rotation = 500 × 3.96 = 1980 m²

Thus, the area of the field pressed in 500 rotations is 1980 m².