Question

5. The curved surface area of a 1 point
cylinder is 440 sq. cm and its
radius is 5 cm. Find its height
O a. 44 cm
O O O
b. 14 cm
O c. 22 cm
O d. 7 cm​

Answer 1

$\LARGE{ \underline{\underline{ \purple{ \sf{Required \: answer:}}}}}$

GiveN:

• Curved surface area = 440 cm²
• Radius of the cylinder = 5 cm

To FinD:

• Height of the cylinder?

Step-wise-Step Explanation:

The area of the curved part of a cylinder can be determined by the formula below:

$\because{ \boxed{ \rm{CSA = 2\pi rh}}}$

Where r is the radius of the cylinder

h is the height of the cylinder.

Putting the values for CSA and r,

⇒ 2πrh = CSA of cylinder

⇒ 2 × 22/7 × 5 × h = 440 cm²

⇒ 220/7 × h = 440 cm²

⇒ h = 440 × 7/220 cm

⇒ h = 14 cm

Thus, the required height of the cylinder is 14 cm. (Ans)

Other Imp. Formulae:

• Volume of cylinder = πr²h
• Total surface area = 2πr(h + r)
• Perimeter of bases = 4πr
• Total base area = 2πr²

Answer 2

Given:-

In a Cylinder

$Curved\:surface \:area {}_{(CSA)}=440cm {}^{2}$

$Radius {}_{(r)}=5cm$

To find:-

Height =h

Solution:-

As we know that in a Cylinder

${:}\longrightarrow$${\boxed {CSA=2 {\pi}rh}}$

[By substituting values ]

${:}\longrightarrow$$2×{\frac{22}{7}}×5×h=440$

${:}\longrightarrow$${\frac {220h}{7}}=440$

${:}\longrightarrow$$h={\cancel{440}}×{\frac {7}{{\cancel {220}}}}$

${:}\longrightarrow$$h=7×2$

${:}\longrightarrow$${\underline{\boxed{\bf {height =14cm}}}}$

Answer:-

${\bigcirc {44cm}}$

${\odot {14cm}}$

${\bigcirc {22cm}}$

${\bigcirc {7cm}}$