Aprojectile is fired straight upward from the earth's surface at the south pole with an initial speed equal to one third the escape speed. (the radius of the earth is 6.38 106 m.)
(a) ignoring air resistance, determine how far from the center of the earth the projectile travels before stopping momentarily. m
(b) what is the altitude of the projectile at this instant? m

7177500 m

797500 m

Explanation:

G = Gravitational constant

m = Mass of projectile

M = Mass of Earth

R = Radius of Earth

h = Altitude

r = Distance from the center of Earth

= Escape velocity

Initial velocity

Kinetic energy at the surface

Potential + Kinetic energy at the surface = Potential energy at the max height

Cancelling G, M, and m

Distance of the max height from the center of earth is 7177500 m

The altitude of the projectile is 797500 m

explanation:

the masses of the objects and the distance between them

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form