Introduction to Free Fall
A free falling object is an object that is falling under the sole
influence of gravity. Any object that is being acted upon only by the
force of gravity is said to be in a state of free fall. There are two important motion characteristics that are true of free-falling objects:
- Free-falling objects do not encounter air resistance.
- All free-falling objects (on Earth) accelerate downwards at a rate of 9.8 m/s/s (often approximated as 10 m/s/s for back-of-the-envelope calculations)
Because free-falling objects are accelerating downwards at a rate of 9.8 m/s/s, a ticker tape trace
or dot diagram of its motion would depict an acceleration. The dot
diagram at the right depicts the acceleration of a free-falling object.
The position of the object at regular time intervals - say, every 0.1
second - is shown. The fact that the distance that the object travels
every interval of time is increasing is a sure sign that the ball is
speeding up as it falls downward. Recall from an earlier lesson, that if an object travels downward and speeds up, then its acceleration is downward.
Free-fall acceleration is often witnessed in a physics classroom by
means of an ever-popular strobe light demonstration. The room is
darkened and a jug full of water is connected by a tube to a medicine
dropper. The dropper drips water and the strobe illuminates the falling
droplets at a regular rate - say once every 0.2 seconds. Instead of
seeing a stream of water free-falling from the medicine dropper, several
consecutive drops with increasing separation distance are seen. The
pattern of drops resembles the dot diagram shown in the graphic at the
right.
FREE FALL
Free
fall is a kind of motion that everybody can observe in daily life. We
drop something accidentally or purposely and see its motion. At the
beginning it has low speed and until the end it gains speed and before
the crash it reaches its maximum speed. Which factors affect the speed
of the object while it is in free fall? How can we calculate the
distance it takes, time it takes during the free fall? We deal with
these subjects in this section. First, let me begin with the source of
increasing in the amount of speed during the fall. As you can guess,
things fall because of the gravity. Thus, our objects gain speed
approximately10m/s in a second while falling because of the gravitation.
We call this acceleration in physics gravitational acceleration
and show with “g”. The value of g is 9,8m/s² however, in our examples
we assume it 10 m/ s² for simple calculations. Now it’s time to formalize what we said above. We talked about the increase in speed
which is equal to the amount of g in a second. Thus our velocity can be
found by the formula;
http://www.physicstutorials.org/home/mechanics/1d-kinematics/free-fall
As I understand free fall was the falling of object by the cause of the gravity.
