Question

the curved surface area of a cylindrical pillar is 220m^2 and its volume in 385m^3. find the diameter and the height of the pillar.​

Answer 1

Answer:

Step-by-step explanation:

Answer 2

The curved surface area of a cylinder (CSA) = 220 m²

The volume of the cylinder = 385 m³

To be found:-

the diameter and the height of the cylinder

CSA = 2πrh

 

⇒ 220 = 2 × 22/7 × rh

⇒ 220 = 44/7 × rh

⇒ 220 × 7/44 = rh

⇒ 35 = rh

 

Now,

Volume = πr²h

⇒ 385 = 22/7 × r × r × h

⇒ 385 = 22/7 × r × rh

⇒ 385 = 22/7 × 35 × r      [as we got rh = 35 ]

⇒ 385 = 110 × r

⇒ 385 ÷ 110 = r

⇒ 3.5 = r

Now,

rh = 35

⇒ 3.5 × h = 35

⇒ h = 35 ÷ 3.5

⇒ h = 10

Therefore

Diameter = 2r = 2 × 3.5 = 7 m

height = 10 m