the velocity v that an object r units from the earths center must have to escape earths gravity is given by…

the velocity v that an object r units from the earths center must have to escape earths gravity is given by $v^{2}=\frac{2gm}{r}$, where g is a constant. solve for the objects mass m.\n\n$m = \frac{2r}{v^{2}g}$\n$m = \frac{v^{2}r}{2g}$\n$m = \frac{2g}{v^{2}r}$\n$m = \frac{2gr}{v^{2}}$
Answer
Explanation:
Step1: Start with the given formula
$v^{2}=\frac{2GM}{r}$
Step2: Isolate $M$
Multiply both sides by $r$: $v^{2}r = 2GM$. Then divide both sides by $2G$: $M=\frac{v^{2}r}{2G}$
Answer:
$M=\frac{v^{2}r}{2G}$ (corresponding to the second - option in the multiple - choice list)