Question

A cylinder is having radius of the base 14
cm and height 30 cm ,then its lateral
surface area is
(a) 3872 cm?
(c) 2640 cm?
(b) 18480 cm?
(d) 3456 cm2​

Answer 1

GIVEN :-

• Radius of cylinder is 14 cm.
• Height of cylinder is 30 cm.

TO FIND :-

• Lateral surface Area ( L.S.A ) = ?

SOLUTION :-

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Lateral surface Area = 2πrh

= 2 × 22/7 × 14× 30

= 2 × 22 × 2 × 30

= 44 × 60

= 2640 cm

Hence Lateral surface Area of cylinder is 2640 cm.

ADDITIONAL INFORMATION :-

$\boxed{\begin{minipage}{6.5 cm}\underline{\text{Some Important Formulae Related to it :}}\\ \\ Area of cylinder = \pi r^2\\ \\Perimeter \of \cylinder = 2\pi r\\ \\ CSA \of\ cylinder = 2\pi rh \\ \\Volume\ of\ cylinder= \pi r^2h\end{minipage}}$

Answer 2

Answer:

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Gɪᴠᴇɴ :-

• The radius (r) of the base = 14 cm
• The height (h) of cylinder = 30 cm

therefore,

lateral surface area (L.S.A) = 2πrh

= 2 × 22 × 14 × 30

7

= 2 × 22 × 2 × 30

= 4 × 660

= 2640

So, the lateral surface of the cylinder is$2640 {cm}^{2}$

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more formulas

Cʏʟɪɴᴅᴇʀ :-

• Area of cross section – πr^2
• Perimeter – 2πr
• Total surface area – 2πr (h+r)
• Volume – πr^2h

Cᴏɴᴇ :-

• l^2 = r^2 + h^2
• Curve surface area = πrl
• Volume = 1/3 πr^2 h
• Total surface area = πr (l+r)

*note— l is slant height

Sᴘʜᴇʀᴇ :-

• Volume = 4/3π r^3
• Total surface area = 4πr^2