Question

two spheres made of the same material have the radii in the ratio 2 :3. find the ratio of their respective masses

Answer 1

ratio of radius of the sphere is 2:3

so r1/r2=2/3

¤ ratio is surface areas =4π(r1)^2/4π(r2)^2

=r1^2/r2^2/

=(r1/r2)^2

so from first r1/r2=2/3

=(2/3)^2

=2^2/3^2

=4/9

hence answer is 4/9

¤ ratio of volume of spheres

= [(4πr^3)/3]/(4πr^3)/3

after cutting =r1^3/r2^3

r1/r2=2/3

so r1^3/r2^3=(2/3)^3

=8/27

Answer 2

Explanation:

r

2

r

1

=

3

2

Since volume α Radius

3

So

V

2

V

1

=(

r

2

r

1

)

3

=

27

8

& they are of same material

hence ϱ

1

=ϱ

2

V

1

m

1

=

V

2

m

2

m

2

m

1

=

V

2

V

1

=

27

8