Find the surface area of a sphere of radius:
i) 10.5 cm  ii) 5.6 cm  iii) 14 cm

Solution:

i) Radius, r = 10.5cm

Surface area of the sphere = 4πr²

= 4 × 22/7 × (10.5cm)²

= 1386 cm²

ii) Radius, r = 5.6cm

Surface area of the sphere = 4πr²

= 4 × 22/7 × (5.6cm)²

= 394.24 cm²

iii) Radius, r = 14cm

Surface area of the sphere = 4πr²

= 4 × 22/7 × (14cm)²

= 2464 cm²

Thus, the surface areas of the sphere of radii 10.5 cm, 5.6 cm, and 14 cm are 1386 cm², 394.24 cm², and 2464 cm² respectively.

☛ Check: NCERT Solutions for Class 9 Maths Chapter 13

Video Solution:

Find the surface area of a sphere of radius: i) 10.5 cm ii) 5.6 cm iii) 14 cm

Class 9 Maths NCERT Solutions Chapter 13 Exercise 13.4 Question 1

Summary:

The surface areas of the sphere of radii 10.5 cm, 5.6 cm, and 14 cm are 1386 cm², 394.24 cm², and 2464 cm² respectively.

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