Question

Find the cost of polishing on a cylindrical tower with radius 7cm and height 15cm at a

rate of Rs. 5 per cm2

​

Answer 1

Answer:

Height of the cylindrical part =13cm

Radius of cone , cylinder and hemi sphere=5cm

r=5cm for hemisphere cylinder and cone.

Height of cone h=30−5−13=12

The area of canvas required=Surface area of hemishphere,cylinder and cone parts of tent

A=2πr

2

+2πrH+πr(

h

2

+r

2

)

A=2π×5×5+2π×5×13+π×5(

5

2

+12

2

)

A=770cm

2