Question

If the lateral surface of a cylinder is 94.2 cm² and its height is 5 cm, then find 

(i) radius of its base 

(ii) its volume (Use π = 3.14)

Answer 1

Here, h = 5 cm, 2πrh = 94.2 cm2. 

(i) 2πrh = 94.2 

⇒ 2 × 3.14 × r × 5 = 94.2 

⇒ r = 94. 2/ 2x 3.14x 5 = 3 

Hence, base radius of the cylinder = 3 cm Ans. 

(ii) Volume of the cylinder = π r²h 

= 3.14 × 3 × 3 × 5 cm³ = 141.3 cm³ Ans