Question

Find the total surface area of a hollow cylinder open at both ends, if its length is 28 cm, external radius is 7 cm and thickness is 1 cm.... Pls answer it fast

Answer 1

Answer:

1282.28

Step-by-step explanation:

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Answer 2

Answer:

• Length of the cylinder = 28 cm
• External radius = 7cm
• Thickness = 1 cm
• Total Surface Area = ?

Diagram

$\setlength{\unitlength}{1.4cm} \thicklines \begin{picture}(2,0)\qbezier(0,0)(0,0)(0,2.5)\qbezier(2,0)(2,0)(2,2.5)\qbezier(0,0)(1,1)(2,0)\qbezier(0,0)( 1, - 1)(2,0) \put(1,1){\line(0,1){1}}\put(1,1){\line(0, - 1){1}}\put(0.2,1){ \sf 28 \: cm }\put(1.1,0.1){ \sf 6 \: cm }\put(1,0){\line(1,0){1}}\qbezier(0,2.5)(1,1.5)(2,2.5)\qbezier(0,2.5)(1, 3.5)(2,2.5)\end{picture}$

$\displaystyle\sf \underline{\bigstar\:\textsf{According to the given Question :}}$

• We shall first find the radius of the cylinder which will be equal to the Difference Between the external and the internal radius.

$\displaystyle\sf :\implies Radius = Outer \ Radius - Inner \ radius$

• Thickness = Inner radius
• Inner Radius = 1 cm
• Outer radius = 7 cm

$\\\displaystyle\sf :\implies Radius = 7-1$

$\displaystyle:\implies\textsf{Radius = \textbf{6 cm}}$

$\displaystyle\sf \underline{\bigstar\:\textsf{TSA of the cylinder :}}$

$\displaystyle\sf \dashrightarrow TSA = 2\pi r(h+r)$

$\displaystyle\sf \dashrightarrow TSA = 2\pi \times r(28+6)$

$\displaystyle\sf \dashrightarrow TSA = 2\pi \times r(34)$

$\displaystyle\sf \dashrightarrow TSA = 2\pi \times 6\times 34$

$\displaystyle\sf \dashrightarrow TSA = 2\pi\times 204$

$\displaystyle\sf \dashrightarrow TSA = 2\times \frac{22}{7}\times 204$

$\displaystyle\sf \dashrightarrow TSA = 2\times 641.2$

$\displaystyle\sf \dashrightarrow\underline{\boxed{\sf TSA = 1282.4 \ cm^2}}$

$\displaystyle\therefore\:\underline{\textsf{The TSA of the cylinder is \textbf{1282.4 cm}}\sf {}^2}$