MENU
Question -

A toy is in the shape of a right circular cylinder with a hemisphere on one end and a cone on the other. The radius and height of the cylindrical parts are 5cm and 13 cm, respectively. The radii of the hemispherical and conical parts are the same as that of the cylindrical part. Find the surface area of the toy if the total height of the toy is 30 cm.



Answer -

Given,

Height of theCylindrical portion (H) = 13 cm

Radius of theCylindrical portion (r) = 5 cm

Height of the wholesolid = 30 cm

Then,

The curved surfacearea of the cylinder (S1) = 2πrh

S1 =2π(5)(13)

S1 =408.2 cm2

Let, ‘L’ be the slantheight of the cone

And, the curvedsurface area of the cone (S2) = πrL

S2 =π(6)L

For conical part, wehave

h = 30 – 13 – 5 = 12cm

Then, we know that

L2 = r2 +h2

L2 = 52 +122

L2 =25 + 144

L2 =169

L = 13 m

So,

S2 =π(5)(13) cm2

S2 =204.28 cm2

Now, the curvedsurface area of the hemisphere (S3) = 2πr2

S3 =2π(5)2

S3 =157.14 cm2

Thus, the total curvedsurface area (S) = S1 + S2 + S3

S = (408.2 + 204.28 +157.14)

S = 769.62 cm2

Therefore, the surfacearea of the toy is 770 cm2

Comment(S)

Show all Coment

Leave a Comment

Free - Previous Years Question Papers
Any questions? Ask us!
NodeJS Interview Questions Answers
ASP.Net Interview Questions Answers
Interview Questions Answers
×