Q.

If R is the radius of the earth and g is the acceleration due to gravity on the earth surface. Then the mean density of the earth will be:              [2023]
 

1 πRG12g  
2 3πR4gG  
3 3g4πRG  
4 4πG3gR  

Ans.

(3)

The relation between acceleration due to gravity and radius of earth is g=GMR2

We know M=ρV

Then, g=43πGRρ or ρ=3g4πGR