Question

a roller takes 750 complete revolutions to move once over a level of road. find the area of road if the diameter of the roller is 84cm and lenght is 1m

Answer 1

d=84cm
=>r= 84/2= 42 cm.
therefore,
l=1m=100cm
area=42*100 sq cm= 4200 sq. cm.
area of the road =4200*750=3375000 sq. cm.

hope the ans is correct

Answer 2

ANSWER

Area of road =750× area covered in 1 revoluation

=750× lateral surface area of cylinder

=750×2πrh

Given,  d=84cm⇒r=42cm→10042m

h=1m

=750×2×722×10042×1

=1001500×132

=1980m2