a large sphere is made by melting 21 balls of radius 2 cm find the volume of new sphere
Answers
Answer:
Step-by-step explanation:
Volume of iron =
3
4
πR
3
=
3
4
π(4)
3
=
3
4
π[64] cm
3
Volume of small sphere =
3
4
π(r)
3
=
3
4
π(2)
3
=8(
3
4
π) cm
3
no. of small spheres that can be formed =
volume of small sphere
volume of big iron
=
8(4/3π)
64(4/3π)
=8
∴ 8 small spheres can be formed.
Surface area of the spheres formed =8×(4πr
2
)
=8×(4π)(4)
=128π cm
2
surface area of all sphere formed is 128π cm
2