Neglecting air resistance, all objects fall to earth at a constant acceleration of 9.80 m/s². This value is known as the gravitational acceleration, g, and it is equal to 32.2 ft/s² in the English system of units. The distance, d, traveled by the object and the time, t, it takes for the object to fall is given by .

d = 1/2at²

t =√2d/g

Explanation:

From the equation of motion; we have s = ut + 1/2 at², when a body continue to move or set at motion the initial velocity of that body becomes 0=u, there by, the resulting equation becomes;

S = ut + 1/2 at² when u= 0

S = 0×t + 1/2 at²

S = 0 + 1/2at²

S = 1/2at² , here s = d, a = g

d = 1/2gt².

The time taken is;

t = √2d/g where d is the distance travelled in one second, g is the acceleration due to gravity.

come closer and become far apart and become steam/gas