Question

A metallic pipe has internal and external diameter 10 cm and 12 CM and its length is 4.2m

find​ its total surface area​

Answer 1

Answer:

$given \\ A \: metallic \: pipe \: has \\ internal \: and \: external \: diameter \: 10 cm \\ and \: 12 CM \: and \: its \: length \: is \: 4.2m</p><p>$

$to \: find \: its \: total \: surface \: area$

$first \: we \: have \: to \: find \: internal \\ curved \: surface \: area \: and \\ external \: curved \: surface \: area$

taking π=3.14

length or height of pipe =4.2cm

=4.2×100

=420cm

as all units are in normal cm so we converted

$internal \: curved \: surface \: area = internal \: circumference \times length$

$by \: substituting \: the \: values \: we \\ get$

$= \pi \: d \times h$

$= 3.14 \times 10 \times 420 \\ = 13188 {cm}^{2}$

$external \: curved \: surface \: area = \pi \: d \times h$

$= 15825.6 {cm}^{2}$

$d \: is \: diameter \: and \: h \: is \: height$

$total \: surface \: area \: of \: pipe = internal \: \\ curved \: surface \: area + external \: curved \: surface \: area$

$on \: substituting \: the \: values \: we \: get$

$= 13188 {cm}^{2} + 15825.6 {cm}^{2}$

$= 29013.6 {cm}^{2}$

therefore total surface area of pipe is 29013cm^2

Step-by-step explanation:

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