Find the important question of exercise 13.3 question number 4 of ncert class 10 chapter surface areas and volumes . What is the best solution of this question , also find the simplest and easiest solution of this question .A well of diameter 3 m is dug 14 m deep. The earth taken out of it has been spread evenly all around it in the shape of a circular ring of width 4 m to form an embankment. Find the height of the embankment.

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# A well of diameter 3 m is dug 14 m deep. The earth taken out of it has been spread evenly all around it in the shape of a circular ring of width 4 m to form an embankment. Find the height of the embankment. Q.4

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The shape of the well will be cylindrical as given below.

Given, Depth (h

_{1}) of well = 14 mDiameter of the circular end of the well =3 m

So, Radius (r

_{1}) = 3/2 mWidth of the embankment = 4 m

From the figure, it can be said that the embankment will be a cylinder having an outer radius (r

_{2}) as 4+(3/2) = 11/2 m and inner radius (r_{1}) as 3/2mNow, let the height of embankment be h

_{2}âˆ´ Volume of soil dug from well = Volume of earth used to form embankment

Ï€Ã—r

_{1}^{2}Ã—h = Ï€Ã—(r_{2}^{2}-r_{1}^{2}) Ã— h_{2}Solving this, we get,

The height of the embankment (h

_{2}) as 1.125 m.