Two objects have masses of 22 MG22MG and 23 MG23MG. How much does the gravitational potential energy between the objects change if the distance between them changes from 25 m25m to 75 m75m?

1 Answer
Mar 3, 2018

The change in gravitational potential energy is =90*10^-5J=90105J

Explanation:

Gravitational potential is the potential energy per kilogram at a point in a field.

So the units are J, "Joules"J,Joules

Phi=-G(M_1M_2)/R

The gravitational universal constant is

G=6.67*10^-11Nm^2kg^-2

The masses causing the field is =M_1 kg and =M_2 kg

The mass is M_1=22MG=22*10^6g=22*10^3kg

The mass is M_2=23MG=23*10^6g=23*10^3kg

The distance between the centers is =Rm

The distance R_1=25m

The distance R_2=75m

Therefore,

Phi_1=(-G*(22*10^3*23*10^3)/25)

Phi_2=(-G*(22*10^3*23*10^3)/75)

So,

Phi_1-Phi_2=(-G*(22*10^3*23*10^3)/25)-(-G*(22*10^3*23*10^3)/75)

=22*23*10^6*6.67*10^-11(1/75-1/25)

=-90*10^-5J