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If the lateral surface of a cylinder is 92.4 cm2 and its height is 5 cm, then find
(i) radius of its base (ii) its volume. (Use π = 3.14)
Since the lateral surface area and height are known, we can easily obtain the radius and its volume.
Lateral surface area (CSA) of a cylinder of base radius r, and height h = 2πrh
The volume of a cylinder of base radius r, and height h = πr2 h
(i) Let the radius of the cylinder be r.
Height of the cylinder, h = 5 cm
Lateral surface area = 92.4 cm2
2πrh = 92.4
r = 92.4 / 2hπ
r = 92.4 / (2 × 5 × 3.14)
r = 3 cm (approx.)
(ii) Volume of cylinder = πr2h
= 3.14 × 3 cm × 3 cm × 5 cm
= 141.3 cm3
Thus, the radius of the base is 3 cm and the volume is 141.3 cm3.
If the lateral surface of a cylinder is 92.4 cm² and its height is 5 cm, then find i) radius of its base ii) its volume. (Use π = 3.14)
NCERT Solutions for Class 9 Maths Chapter 13 Exercise 13.6 Question 4
It is given that the lateral surface of a cylinder is 92.4 cm2 and its height is 5 cm. We have found that the radius of the base is 3cm and the volume is 141.3 cm3.
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