Question

the radius of moon is 1/4th and mass is 1/80th times as that of earth respectively. if g is the a/c to gravity at earth surface, the value of surface of moon will be?

Answer 1

g = G M / r^2

Now

g(moon ) = (GM / 80 ) / ( r / 4 )^2

gmoon =16 GM / 80 r^2

g moon = GM / 5 r^2

now g moon = 1/5 g