Question -
Answer -
Given,
Inner radius of thewell = 4 m
Depth of the well = 14m
We know that,
Volume of the cylinder= π r2h
= π × 42 ×14 …. (i)
From the question,it’s told that
The earth taken outfrom the well is evenly spread all around it to form an embankment
And, the width of theembankment = 3 m
So, the outer radiusof the well = 3 + 4 m = 7 m
We know that,
Volume of the hollowembankment = π (R2 – r2) × h
= π × (72 –42) × h …… (ii)
On equating both theequations (i) and (ii), we get
π × 42 ×14 = π × (72 – 42) × h
h = 42 ×14 / (33)
h = 6.78 m
Therefore, the heightof the embankment so formed is 6.78 m.