Question

A cylinder,cone and a sphere have same radius and same height.find the ratio of their total surface area.


please help .Need answer urgent​

Answer 1

Answer:

3 cones = 1 cylinder

3:1 issssssssssss

Answer 2

Answer:

$4:4: \sqrt{} 5$

Step-by-step explanation:

Since, the height of a sphere is the diameter, the cone and cylinder have height 2r.

Then

Curved surface area of Sphere=4πr²

Curved surface area of cylinder =2πr(2r)=4πr²

Curved surface area of cone = πrl

where,

$1 = \sqrt{} (r2 +h 2 )= </p><p> (r2+(2r) 2 )= </p><p> \sqrt{} 5r </p><p>2</p><p> </p><p> </p><p> =r </p><p> \sqrt{} 5$

⇒ Curved surface area of cone =π

5r

2

$=π \sqrt{} 5r2$

Now,

ratio of CSA 's a sphere ,cylinder and a cone =

$= 4πr2:2πrh:πrl</p><p></p><p>=4πr2:4πr2:πr2 \sqrt{} 5</p><p></p><p>=4:4: \sqrt{} 5</p><p></p><p></p><p>$