Question

Plz help me to solve this

Answer 1

internal diameter is 50 cm
length of pipe h is 140 cm
internal radius r2is 50/2=25cm
thickness =2cm
outer radius r1 =25+2=27cm
volume = 22/7×140{(27)^2-(25)^2}
=22/7×140×(729-625)
=22×20×104
=45760 cm^3

Answer 2

Given

internal diameter = 50 cm

length of pipe (height) = 140 cm

the pipe is made up of 2 cm thick iron

so,

the external diameter = 50 + 2 + 2 = 54 cm

radius = diameter ÷ 2

Internal radius (of internal diameter) = 50 ÷ 2

= 25cm.

External radius (of external diameter) = 54 ÷ 2

= 27 cm.

Volume of whole pipe (with the volume of iron) of  external radius =

= $= \pi {r}^{2} h \\ \\ = \frac{22}{7} \times( {27})^{2} \times 140 \\ \\ = 22 \times 27 \times 27\times 20 \\ \\ = {320760}cm^{3}$

volume of empty space inside the pipe

of internal radius

= $= \pi {r}^{2} h \\ \\ = \frac{22}{7} \times ( {25})^{2} \times 140 \\ \\ = 22 \times 25 \times 25 \times 20 \\ \\ = {275000}cm^{3}$

now volume of iron in it

= volume of whole pipe - volume of empty space inside

= 320760 - 275000

= 45760

$\bf so \\ the \: volume \: of \: iron \: is \:{45760}cm^{3}$