Question

A solid is in the form of a right circular cylinder with hemispherical ends.the total height of the solid is 35 cm.the diameter of the cylinder is 1/4 of its length.the surface area of the solid is

Answer 1

Let radius of the cylinder be r cm and height = h cm

Then, r = h8 given 

and h = 35 - 2r = 35 - 2 × h8

=> h + h4 = 35 => 5h4 = 35

=> h = 35×45 = 28 cm

∴ r = h8 = 288 = 72 cm

∴ Radius of the hemisphere = 72 cm 

Total surface of area the solid 

= (2 πrh + 2 \times 2 πr2 )sq. cm. 

= 2 π r (h + 2r) sq. cm.

= 2×227×72×(28+2×72)sq.cm 

= 2 × 227 × 72 × 35 sq.cm

= 770 sq.cm