Question

The radius of a well is 1.4 m and its depth is 10 m. Find the quantity of soil that had been taken out to dig the well.​

Answer 1

Given :-

• The radius of a well is 1.4 m

• The depth of well is 10 m.

To Find :-

• The quantity of soil that had been taken out to dig the well.

Understanding the concept :-

We have given the radius and height of the well which is in cylindrical shape. So, the quantify of soil that had been taken out to dig the well is same as Volume of cylinder of given radius and height.

Formula Used :-

$\boxed{\sf \: Volume_{(cylinder)} \: = \: \pi \: {r}^{2} h}$

$\large\underline{\bold{Solution-}}$

Given that

• Radius of cylindrical well, r = 1.4 m

• Depth of cylindrical well, h = 10 m

So,

• The quantity of soil that had been taken out to dig the well = Volume of cylindrical well

$\sf \: Volume_{(cylindrical \: well)} = \pi \: {r}^{2} h$

$\sf \: Volume_{(cylindrical \: well)} = \dfrac{22}{7} \times 1.4 \times 1.4 \times 10$

$\bf\therefore \: Volume_{(cylindrical \: well)} = \: 61.6 \: {m}^{2}$

Additional Information :-

$1. \: \: \boxed{ \bf{CSA_{(cylinder)} = 2\pi \: rh}}$

$2. \: \: \boxed{ \bf{TSA_{(cylinder)} = 2\pi \: r(h + r)}}$