Question

iv) Radii of three solid spheres are 3cm, 4cm and 5cm. Find the
radius of the new sphere which is made hy melting the three
spheres​

Answer 1

Step-by-step explanation:

ANSWER

Volume of solid sphere =

3

4

π[R

1

3

+R

2

3

+R

3

3

]

⇒

3

4

πR

3

=

3

4

π[3

3

+4

3

+5

3

]⇒R

3

=216⇒R=

3

216

=6cm

∴ Radius of solid sphere =6cm

Answer 2

Step-by-step explanation:

Let the radius of new sphere be R.

Radii of three solid spheres are:

r1=3cm

r2=cm

r3=5cm

Volume of sphere of radius R = volume of radius r1 + volume of radius r2+ volume of radius r3

4/3 pieR³ =4/3 pie r1³+ 4/3 pie r2³ + 4/3 pie r3³

4/3 pieR³= 4/3 pie (r1³ + r2³ + r3³)

R³= r1³+ r2³ + r3³

R³= 3³ + 4³ + 5³

R³= 27 + 64 + 125

R³= 216

R = 6 cm