If R is the radius of the earth and g is the acceleration due to gravity on the earth surface, the mean density of the earth is
Options
(a) 4πG/3gR
(b) 3πG/4gR
(c) 3g/4πRG
(d)πRg/12G
Correct Answer:
3g/4πRG
Explanation:
Density = Mass/ Volume
= M / (4/3 π R³)
= (gR² / G). x 3/4 (1/π R³) [as g = GM/R²]
= (3/4π G) x (g/R)
=3g/4πRG