Newtons Laws EX 38

The strength of the gravitational field is also called the gravitational acceleration. The gravitational acceleration of a particle which is placed at some distance $r$ from an object of mass $m$ is equal to:

$g={Gm \over r^{2}}$

where $G=6.67\times 10^{-11}$.

(a) Neptune: $g={(6.67\times 10^{-11})(1.03\times 10^{26}) \over (2.43\times 10^{7})^{2}}=11.6m/s^{2}$

(b) Jupiter: $g={(6.67\times 10^{-11})(1.9\times 10^{27}) \over (7.14\times 10^{7})^{2}}=24.8m/s^{2}$

(c) Neutron star: $g={(6.67\times 10^{-11})(10^{30}) \over (2\times 10^{4})^{2}}=1.67\times 10^{11}m/s^{2}$