A well with 10 m inside diameter is dug 8.4 m deep. Earth taken out of it is spread all around it to a width of 7.5 m to form an ambankment. Find the height of the embankment.

Question

Philoid · Accepted Answer

Given,

Inside diameter of well = 10 m

So, inside radius of well =

Depth of well = 8.4 m

Earth spread out at height up to = 7.5m

So, outer radius R = 7.5+5= 12.5 m

Let height of embankment = H meter

So ,

volume of earth in embankment = volume of earth dug out

= π(R² –r²) = πr²h

= π(12.5² – 5²) ×H = π×5²×8.4

= 17.5×7.5×H = 25×8.4

=