Question

A person standing on the surface of the earth has a weight of 650 N. What is its weight at a distance of two earth radii from the surface? If the person is at a distance of two earth radii from the surface, he/she is at a distance of three earth radii from the earth’s center. Since we have an inverse square law, three times the distance means 1/9th of the weight.

Answer 1

72.22 N

Step-by-step explanation:

F = weight

m = mass of body

M = mass of earth

R = radius of earth

G = universal constant of gravitation

F_1= 650 N

F_1 = GMm/R^2

two earth radius above the surface of the earth:

F_2= GMm/(3R)^2= GMm/9R^2= F_1/9= 650/9

=72.22 N