Another Physics question about radius

Question

How much would a 100-kg object weigh at one earth’s radius above the earth?

Answer 1

On the earth's surface, W = mg

According to Newton's Law of Gravitation

F = G M_e m / r²

If the distance between the object (100 kg mass) and the center of the earth is doubled (altitude = R_e) then the force is reduced by a factor of 2² or 4.

W = 0.25 mg = 0.25 (100)(9.81) = 245 N

Answer 2

Consider that weight is actually the effect of the Earth's gravitational pull on the object. This is generally given by

Weight = force due to the gravitational pull between two objects = GMm/R^2. Where G is the gravitational constant, M is the mass of one object, m is the mass of the other object, and R is the distance between their centers. So, here what is M and m? M = mass of the Earth and m = 100 kg. And, what is R? R = radius of the Earth + radius above the Earth. Now you just plug and chug.