A well of diameter 14m is dug 8m deep. The earth taken out of it is evenly spread all around it to a width of 21 m to form an embankment. Find the height of the embankment( in cm).
Volume of earth dug out from the well = πr2h=227×7×7×8=1232m3
Area of the embankment = 227×(R2−r2)=227×((28)2−(7)2)m2=227×35×21=2310m2 .
Height of the embankment = Volume of earth dug outarea of embankment = 12322310×100cm
= 53.3 cm