Question

Calculate
(i) The total surface area area and
(ii) Curved surface area
If height is 21 cm and cylinder of radius 14 cm​

Answer 1

Answer:

(i) TSA =

(ii) CSA =

Step-by-step explanation:

TSA of cylinder = 2πrh

=> 2*22/7*14*21 = 2*22*2*21 = 1848 cm²

CSA of a cylinder = 2πr(r+h)

=> 2*22/7*14*35 = 2*22*2*35 = 3080cm²

Answer 2

$\large{\red{\bold{\underline{Given:}}}}$

$\sf \: Radius \: of \: the \: cylinder = 14cm \\ \\ \sf \: Height \: of \: cylinder = 21cm$

$\large{\green{\bold{\underline{To \: Find:}}}}$

$\sf \: (i) \: Total \: surface \: area \: of \: cylinder \\ \\ \sf \: (ii) \: Curved \: surface \: area \: of \: cylinder$

$\large{\blue{\bold{\underline{Formula \: Used:}}}}$

$\sf \: Total \: surface \: area = 2\pi r(r + h) \\ \\ \sf \: Curved \: surface \: area = 2\pi rh$

$\large{\red{\underline\bold{{Solution:}}}}$

$\sf \: Let \: the \: radius \: of \: the \: cylinder \: be \: r, \\ \sf \: and \: the \: height \: of \: the \: cylinder \: as \: h$

$\large{\green{\bold{\underline{Then:}}}}$

$\sf \: (i) \: Total \: surface \: area = 2\pi r(r + h) \\ \\ \rightarrow \: \sf Total \: surface \: area = 2 \times \frac{22}{7} \times 14(14 + 21) \\ \\ \rightarrow \: \sf Total \: surface \: area = 2 \times \frac{22}{7} \times 14(35) \\ \\ \rightarrow \: \sf \: Total \: surface \: area = \frac{44}{\cancel7} \times \cancel14 \times 35 \\ \\ \rightarrow \: \sf \: Total \: surface \: area = 3080 \: {cm}^{2}$

$\large{\pink{\bold{\underline{Now:}}}}$

$\sf \: (ii) \: Curved \: surface \: area = 2\pi rh \\ \\ \rightarrow \: \sf \: Curved \: surface \: area = 2 \times \frac{22}{7} \times 14 \times 21 \\ \\ \rightarrow \: \sf \: Curved \: surface \: area = 2 \times \frac{22}{\cancel7} \times \cancel14 \times 21 \\ \\ \rightarrow \: \sf \: Curved \: surface \: area = 44 \times 2 \times 21 \\ \\ \rightarrow \: \sf \: Curved \: surface \: area = 1848 \: {cm}^{2}$

$\large{\orange{\bold{\underline{Therefore:}}}}$

$\sf \: The \: total \: surface \: area \: of \: cylinder \: is \\ \sf \: 3080 {cm}^{2} \: and \: curved \: surface \: area \: is \: 1848 {cm}^{2}.$