Question

Metallic spheres of radii 6cm,8cm and 10cm are melted and recasted into a single solid sphere.find the surface area of the solid apherw formed

Answer 1

Let the radius of sphere formed be R

r1 = 6cm
r2 = 8cm
r3 = 10cm

sum of volume of three metallic sphere = volume of the sphere recasted

4/3πr1^3 + 4/3πr2^3 + 4/3πr3^3 = 4/3πR^3

4/3 π ( r1^3 + r2^3 + r3^3) = 4/3 π R^3

r1^3 + r2^3 + r3^3 = R^3

6^3 + 8^3 + 10^3 = R^3

216 + 512 + 1000 = R^3

1728 = R^3

12 cm = R = radius of recasted sphere

Surface area of recasted sphere = 4πR^2

= 4 × 22/7 × 12 × 12

Ans. Surface area of recasted sphere = 1810.28 cm^2

Answer 2

HOPE IT HELPS YOU...

PLEASE FOLLOW ME