The diameter of a roller is 84cm and its length is 120cm. It takes 500 complete revolutions to move once over to level a playground. Find the area of the playground in m 2 .
Given: diameter , d= 84cm and its length , h= 120cm
Since a roller is in cylindrical shape.
Height (h) of cylindrical roller = Length of roller = 120 cm
Radius (r) of the circular end of roller =
CSA of roller = 2πrh
∴Area of field = 500 × CSA of roller
= (500 × 31680) cm2
= 15840000 cm2
= 1584 m2
Thus, area of the playground = 1584 m2