Question

A hollow cylindrical tube open at both the ends is made up of 2cm thick iron . If the external diameter is 50 cm and length of tube is is 140cm . Find cubic cm of iron in it . Find the weight of tube , if 1cu m of metal is 8 g.

Answer 1

$\huge \mathfrak \orange{question}$

A hollow cylindrical tube open at both the ends is made up of 2cm thick iron . If the external diameter is 50 cm and length of tube is is 140cm . Find cubic cm of iron in it . Find the weight of tube , if 1cu m of metal is 8 g.

$\huge \mathfrak \orange{answer}$

$\bold{external \: radius = } \sf{25cm} \\ \\ \bold{thickness \: of \: metal= } \sf{2cm} \\ \\ \bold{inner \: radius = } \sf{25 - 2= 23}$

$\bold{volume \: of \: iron \: = \: outer \: volume - inner \: volume}$

$\implies \sf{ \frac{22}{7} \times 25 \times 140 - \frac{22}{7} \times 23 \times 23 \times 140} \\ \\ \implies \sf{ \frac{22}{7} \times 140(625 - 529) \times 22 \times 20 \times 96cm } \\ \\ \implies \: \: \sf{42240 {cm}^{3} } \\ \\ \implies \: \: \sf{weight \: of \: cube \: = 42240 {cm}^{3} } \\ \\ \boxed {\implies{ \frac{42240 \times 8}{1000}kg = 337.92kg - > answer }}$