If the distance from the Earth’s center to the Moon’s center were suddenly doubled, what would occur to the gravitational force between them? (A) Gravitational force would decrease by a factor of 4.
(B) Gravitational force would increase by a factor of 4.
(C) Gravitational force would decrease by a factor of 2.
(D) Gravitational force would increase by a factor of 2.

A5 foot by 5 foot box culvert is buried 6 feet beneath the surface of the ground. a crosssection of this very long culvert (into and out of the page) is illustrated below. assume that the soil in which the culvert is buried has the following properties: jt = 120 pcf, w = 12%, ko = 0.50, ka = 0.33, and kp = 3.00. calculate the total horizontal force per unit length of culvert (fh) felt on one of the vertical faces of the culvert.