Question

mayank made a bird bath for his garden in the shape of a cylinder with a hemispherical depression at one end .the height of the cylinder is 1.45m and its radius 30 cm .find the total surface area of the bird bath

Answer 1

Height , h = 1.45 m
Radius , r = 30 cm = 0.3 m

Total Surface area of the bird bath = T.S.A of Cylinder

T.S.A of Cylinder = 2πr(r+h)
= 2 × 22 / 7× 0.3 (0.3 +1.45)
= 3.3 m²


As the cylinder is attached to a hemispherical depression , its area is not added.If the cylinder was attached to a base , it would have been calculated...

Answer 2

Answer:

3.3 m^2

Step-by-step explanation:

Let r be the common radius of the cylinder and hemisphere and h be the height of the hollow cylinder.

Then r=30cm;h=1.45m=145cm

Total surface are of the bird-bath = curved surface area of the cylinder + curved surface area of the hemisphere

=2πrh+2πr ^2

=2π(h+r)

=2× 22/7 × 30(145+30)cm ^2

=3.3m^2

hope it is helpful ....