Two identical solid copper sphere of radius R are placed in contact with each other. The gravitational force between them is proportional to.

Explanation

The gravitational force ` F = (G(M)(M))/((2R)^(2)) = (G(4/3 piR^(3)rho))/(4R^(2))`
Mass of the sold sphere `M = 4/3 piR^(3)rho`
` F = (G(16pi^(2)R^(6)rho^(2)))/(9xx 4xx R^(2))`
`F = 4/9 Gpi^(2)rho^(2)R^(4)" , "F prop 4/9 pi^(2) rho^(2) R^(4)`
` :. ` The gravitational force between them is propor tional to 4th power of radius .