Question

What happen to the acceleration due gravity of moon if it is expanded to the size of earth without changing it mass

Answer 1

Answer:  Earths gravitational acceleration would go from 9.8 meters per second per second to 137 meters per second per second.

a=GMr2

G=6.6726x10−11N−m2/kg2 universal gravitational constant

M=Mass

r=radius

Now an interesting thing would happen if the earth was compressed into a 179 kilometer diameter ball. Any more material added to the Earth at this point would make the Earth smaller in diameter but denser in mass. This is the critical point of electron degeneracy in which the volume of an object cannot get bigger as gravity compresses matter more than it pushes back (unless you add tons of heat). Gravity at this size would be 49,262 meters per second per second.