Acceleration due to gravity on the moon is 1/6th of the acceleration due to gravity on the earth. If the ratio of densities of the earth and the moon is 5/3, then radius on the moon in terms of radius of earth will be
We know g=4πGρr3=Kρr
Given, gm=16ge
⇒ gmge=ρmrmρere=16
Also ρm=35ρe
So, 3rm5re=16
⇒rm=5re18