A planet has the same average density as Earth but radius 2 $R_E.$ Compared with Earth, which statements are correct?
Select all that apply

Question

A planet has the same average density as Earth but radius 2R_E. Compared with Earth, which statements are correct?

G1 Physics · Accepted Answer

For equal density M∝R³. Thus g=GM/R²∝R, so g doubles. Escape speed √(2GM/R)∝R, so it doubles. |V|=GM/R∝R², so it becomes four times.