Physics

Problem

Four hypothetical planets have the following ratios of mass

(M)

and radius

(R)

compared with the Earth (

M_E, R_E

): A.

M=\tfrac{1}{4}M_E,\;R=\tfrac{2}{3}R_E

M=\tfrac{1}{9}M_E,\;R=\tfrac{1}{3}R_E

M=\tfrac{1}{12}M_E,\;R=\tfrac{1}{2}R_E

M=\tfrac{1}{81}M_E,\;R=\tfrac{1}{3}R_E

On which planet would your weight be exactly one-ninth of your weight on Earth? a) Planet A b) Planet D c) Planet C d) Planet B