An object is falling from a height of d and reaches a final velocity of vf. Calculate velocity when the object has fallen a distance d/2.

The final velocity, , is gd.

Explanation:

The condition here is a free falling object. Thus from the third equation of motion under free fall, we have;

= + 2gs

where is the final velocity of the object, is the initial velocity of the object, g is the gravitational force and s is the height.

Since the object falls from a height of d, then = 0 m/s, and s = d.

So that;

= 0 + 2gd

   = 2gd

= 2gd

When the distance is , = 0 m/s.

Then;

= 2g

= g x d

When the object falls through the height , then the final velocity is gd.