Question

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.

Answer 1

The final velocity,
`v_(f)`, is gd.

Step-by-step explanation:

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

`v_(f)` =
`v_(i)` + 2gs

where
`v_(f)` is the final velocity of the object,
`v_(i)` 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
`v_(i)` = 0 m/s, and s = d.

So that;

`v_(f)` = 0 + 2gd

= 2gd

`v_(f)` = 2gd

When the distance is
`(d)/(2)`,
`v_(i)` = 0 m/s.

Then;

`v_(f)` = 2g
`(d)/(2)`

`v_(f)` = g x d

When the object falls through the height
`(d)/(2)`, then the final velocity is gd.