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 = $\frac{0.9}{2}$ = 0.45 m

Now,

Area of the field pressed in one rotation = Curved surface area of the road roller

= 2$\mathrm{\pi }$rh

= $2\times \frac{22}{7}\times 0.45\times 1.4$

= 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.