The formula for force of attraction between any two bodies in the universe
F = GMm / r^2. (Newton's Universal law of Gravitation).
G = Universal gravitational constant, G = 6.67 * 10 ^ -11 Nm^2 / kg^2.
M = Mass of first object. = 5.97 x 10^24 kg.
m = mass of second object = 50 kg.
r = distance apart, between centers = in this case it is the radius of the earth
= 6.38 x 10^6 m.
( Sorry I could not assume with the values you gave).
(Actually the force of attraction between an object on the Earth and the Earth is the weight of the object our answer should be around 500N which is from mg = 50 *10 = 500)
So F = ((6.67 * 10 ^ -11)*(5.97 x 10^24)*(50)) / (6.38 x 10^6)^2.
Punch it all up in your calculator.
F = 489. 135 N.
Remember we said it would be around 500.
So that's our answer.
F = 489. 135 N. Hurray!!
