if the weight of a spherical shell is 7/8th of what it would be , if it were a solid shell . the ratio of inner radii is ?

• 1:2
  
  let outer radius of the sphere be R and density be d
  volume of solid sphere=(4/3)*pi*R^3
  weight of solid sphere=[(4/3)*pi*R^3]*d
  
  let inner radius of hollow sphere be r
  volume of hollow sphere=(4/3)*pi*(R^3-r^3)
  weight of hollow sphere=[(4/3)*pi*(R^3-r^3)]*d
  
  according to question:
  [(4/3)*pi*(R^3-r^3)]*d=(7/8)*[(4/3)*pi*R^3]*d
  (R^3-r^3)=(7/8)*R^3
  (1/8)*R^3=r^3
  r^3/R^3=1/8
  r/R=1/2
  ratio of inner radius to outer radius=1:2
• 8 years agoHelpfull: Yes(0) No(0)