physics
posted by Bella .
can someone please help me with this question quick...
Which of the following equations expresses Newton's law of universal gravitation?
a. Fc=MVt^2/r
b. Fg=M1M2/r
c. g=Gme/r^2
d. Fg=Gmme/r^2
i really need help..thanks:)

Two of the equations deal with the force of gravity. If the "g" is answer d. is a subscript, it is the formula for the gravitational force (weight) of an object of mass m at a distance r from the center of the earth.
Equation c. is also a correct equation for the acceleration of gravity (g) for an object located r from the center of the earth.
Both c. and d, are correct, but not really "universal" since they only deal with the gravity field of the earth.
So all of these choices are flawed in one way or another. 
which do you think would be the best pick for me

dont know did u find out the answer?