Question

a solid sphere of radius 3 cm is of mass 9 kg. find the mass of the sphere of the same material of radius 5 cm​

Answer 1

Radius of the sphere = 3cm

Mass = 9kg

Voume of the sphere = 4/3πr³

= 4/3 π (3)³

= 4/3 π 27

= 4×9 π

= 36π cm³

Mass per unit volume = 9 / 36π Kg cm-³

Now if New sphere has radius = 5cm

Volume = 4/3 π ( 5 )³

= 4/3 π × 125

= 500π / 3 cm³

Mass of new sphere = volume × mass per unit volume

= ( 500π / 3 ) × ( 9 / 36π ) kg

= ( 500π / 3 ) × ( 1 / 4π )

= 500 / 12

= 41.66 kg

Hope the solution is clear to you!!

Answer 2

3cm of mass of 9kg and mass of sphere of the same material of radius 5cm=25cm