Two objects have masses of 32 MG32MG and 23 MG23MG. How much does the gravitational potential energy between the objects change if the distance between them changes from 7 m7m to 32 m32m?

1 Answer
Mar 20, 2018

The change in gravitational potential energy is =547.9*10^-5J=547.9105J

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=32MG=32*10^6g=32*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=7m

The distance R_2=32m

Therefore,

Phi_1=(-G*(32*10^3*23*10^3)/7)

Phi_2=(-G*(32*10^3*23*10^3)/32)

So,

Phi_1-Phi_2=(-G*(32*10^3*23*10^3)/7)-(-G*(32*10^3*23*10^3)/32)

=32*23*10^6*6.67*10^-11(1/32-1/7)

=-547.9*10^-5J