Question

The length of metallic pipe is 70cm Inner diameter is
10 cm and thickness is 5 mm. density of
Metal used is 8g /cm, then find the mass of the pipe

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Answer 1

$\\ \blue{\huge{\underline{\overline{\mid{\bold{\purple{ \: \: \: Solution: \: \: \: \blue{\mid}}}}}}}} \\ \\ \\ \\ \bf Length= 70 \: cm \\ \\ \bf</p><p></p><p>I nner \: diameter= 10 \: cm</p><p> \\ \\ \bf</p><p>I nner \: radius= 5 \: cm \\ \\ </p><p> \bf</p><p>T hickness=5 \: mm \\ \bf \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: =0.5 \: cm</p><p> \\ \\ \bf</p><p>Outer \: radius= inner \: radius + thickness \\ \\ \bf</p><p></p><p>Volume \: of \: Cylinder= π(outer \: radius)(height) \\ \bf \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: </p><p></p><p>= \frac{22}{7} \times 5.5 \times 70 \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: </p><p> \bf= 6650 \: cm {}^{3} \\ \\ \bf </p><p>Density= \frac{Mass}{Volume} \\ \bf</p><p></p><p>Density \times Volume=Mass \\ \bf</p><p></p><p>8 \times 6650= mass \\ \bf</p><p> Mass</p><p>=53240g</p><p></p><p>$

Answer 2

$step \: by \: step \: eplanatation \\ \: \: \\ Diameter \: of \: the \: outer \: \: circle \: \ is \: 70 \: cm </p><p> \\ </p><p>Radius \: of \: the \: outer \: circle \: \: \:is \: 70/2 = 35 \\ </p><p></p><p>Given \: Thickness \: is = 10 cm</p><p></p><p> \\ Radius \: of \: the \: inner \: circle = </p><p></p><p>r = - 10 = 25 \: \\ length \: of \: the \: pipe = 5m = 500cm \\ hence \: volume \: of \: the \: pipe \: \pi \: r ^{2}h \: - \pi \: r ^{2}h \\ \pi \: h( {r}^{2} - r ^{2} ) \\ \pi h(r + r)(r - r) \\ 3.14 \times 500(35 + 25)(35 - 25) \\ 3.14 \times 500 \times 60 \times 10 \\ v = 942478 \: cm ^{3} \\ given \: density \: of \: metal \: 8g |cm^{3} \\ we \: know \: that \: mass \: is \: defined as \: the \: product \: of \: volume \: and \: density \: \\ mass \: = volume \times density \\ 942478 \times 8 = 7539824 \: grams$

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