Question

A geyser is cylindrical in shape whose diameter is 28 cm and height 1.5 m. Neglecting the thickness of its walls, calculate its outer curved surface area.

Answer 1

Given:

Diameter = 28 cm ⇒ radius r = 14 cm.

Height = 1.5 m = 150 cm.

take π = `22/7` for exact arithmetic

Outer curved surface area (L.S.A.) = 2πrh = 2 × `22/7` × 14 × 150

= 4200π cm²

= 2 × `22/7` × 14 × 150

= 13200 cm²