Question

A 20m deep well with diameter 7m is dug and the earth dug out is evenly spread out to form acuboidalplatform of base 22m by 14m.Find the height of the platform.

Answer 1

Answer:

It is given that the shape of the well is in the shape of a cylinder with a diameter of 7 m

So, radius = 7/2 m

Also, Depth (h) = 20 m

Volume of the earth dug out will be equal to the volume of the cylinder

Let the height of the platform = H

Volume of soil from well (cylinder) = Volume of soil used to make such platform

π×r2×h = Area of platform × Height of the platform

We know that the dimension of the platform is = 22×14

So, Area of platform = 22×14 m2

∴ π×r2×h = 22×14×H

⇒ H = 2.5 m

Answer 2

Step-by-step explanation:

the well is in a cylindrical shape, here well diameter 7 meter, so radius r= 7/2 meter, height = 20 m

when we dug the well , the volume of the digging well is equal to cuboidal platform volume.

let height of the platform ' h' says

volume of well= volume of platform

πr2h=lbh

22/7×7/2×7/2×20=22×14×h

770= 22×14×h

70=28h

h=2.5 meters