Physics

Problem

1.5\times10^{3}\,\text{kg}

spacecraft is located a distance

r

from the center of a small moon of mass

7.4\times10^{22}\,\text{kg}

. The spacecraft–moon system has a gravitational potential energy of

-6.0\times10^{9}\,\text{J}

(zero at infinite separation). What is

r

? a)

7.4\times10^{5}\,\text{m}

1.2\times10^{7}\,\text{m}

1.2\times10^{6}\,\text{m}

2.5\times10^{6}\,\text{m}