Question 11: Is not inertia the reason for objects same rate-of-fall?

Greetings Ethan:

After reading the first
article about inertia, I have uncovered a problem. I learned in school
some time ago that different sized objects fall at the same rate for the
following reason: a more massive object has more inertia that needs to be
overcome so its greater weight is no more effective in causing acceleration than
is the lesser weight of a less massive object with its lesser inertia. The
problem is that now that I understand that inertia is an inert property of
matter
force and as such could never be the cause of any such event, I am left unsure
as to the reason why objects fall at the same rate here on earth. Do you
have the answer? J. T., Dallas, Texas, USA.

**Thanks for the question, J.T.: **

One often reads of how inertia needs to be overcome before acceleration can
commence. Now that we recognize the truth as presented in
Article I, that
inertia is an imaginary concept that
has no actual role in physics, one may wonder exactly what is meant by this
"overcoming" prediction. I wonder if there is some experiment that shows that a
weak action force can be applied to
the exterior of a weightless object in a vacuum with this force being
insufficient to "overcome" the object's supposed resistance resulting in no
acceleration for the object. Logically this must be
the case if only a stronger force is successful in causing acceleration for the
object. Anything less than this stronger force should certainly be unable to
cause acceleration for the object if there
is any validity to this "overcoming" prediction.

I propose an experiment inside the enclosed cargo bay of the orbiting Space
Shuttle. The test object is a massive cast iron blacksmith's anvil which is
relatively easy to position in front of an
astronaut since the anvil is weightless. Being weightless means that the anvil
is not freely bearing with any force against any other object. Once the anvil,
with its large theorised level of inertia
or whatever that is thought to be in need of "overcoming", is in position
before the astronaut, I will direct the astronaut to very gently push on the
anvil with the tip of a bird's wing feather. Surely
this miniscule Type 3 external force from the feather's slightly-bent tip will
be of a magnitude that is insufficient to "overcome" the massive cast iron
anvil's imaginary inertia. From my
perspective, if the "overcoming" prediction is correct then no observable
acceleration will occur to the weightless but massive anvil due to the steady
but light push from the feather's tip.

Do you think this physical experiment will prove that the anvil will remain
motionless in front of the astronaut while being pushed ever-so-gently by the
feather? No? You are exactly right.
Even the slightest force from the feather's tip will immediately begin causing
slight acceleration for the cast iron anvil in full accord with Newton's grand
formula acceleration = Force / mass.
Here is proof that nothing is present within the anvil's matter that is
attempting to prevent, or successful in preventing, acceleration from occurring
up to the point where some imagined threshold
of inertia force is exceeded or "overcome". Instead the slight force from the
feather's tip reveals the truth of this event, that the "overcoming" prediction
has no basis in reality making it every bit
as unreal and Newton's definition for imaginary inertia.

While you may think that I have gotten lost in answering your question, J.T., I
want you to know that you have already been presented with the answer as to why
different objects on Earth fall at
the same rate. It is not as complicated as one might think. But rather than
point out the answer just yet, I want to discuss the reasoning behind the
answer.

I propose an experiment on Earth where different objects will experience
horizontal acceleration at the rate of 32 feet/sec/sec. The forces of air
friction can be eliminated if the test object is
accelerated on a rail-mounted cart with the object enclosed under the cart's
plastic canopy. Each object tested will be spherical or ball-shaped and free to
roll up to and bear against the rear
bulkhead during the cart's forward-directed acceleration. A compression spring
scale that is attached to this rear bulkhead will measure the forward-directed
acceleration/Action force applied
through the scale to the test object as well as the test object's
rearward-directed acceleration/Reaction force of weight that it will freely and
reactively bear back against the scale.

Sphere 1 will be composed of lead with a mass attribute of 1 lb.m. A weighing
of Sphere 1 at the test site will indicate a weight of 1 lb.f. At this point we
know that if suddenly left unsupported,
Sphere 1's 1 lb of Earth gravitational weight will immediately become a 1 lb
acceleration/Action force as it begins causing downward-directed acceleration
for Sphere 1 at the rate of 32 ft/s/s.
Accordingly, it is easy to predict that when being accelerated horizontally in
the rail-mounted cart, if the onboard scale indicates that an exact 1 lb
acceleration/Action force is being applied in
the forward direction against the back of Sphere 1, then Sphere 1, along with
the cart, is accelerating horizontally at the rate of 32 ft/s/s.

So far, it may seem that all I am doing is pointing out the obvious. If
Newton's formula is applied to this event the U.S. lb.force units need to be
converted to U.S. absolute Poundal force units
at the ratio of 1 lb.f = 32 Poundal. Thus acceleration = Force / mass becomes
acceleration = 32 P / 1 lb.m resulting in acceleration = 32 ft/s/s.

Now if Sphere 1 is replaced in the cart by Sphere 2 made of aluminum with its
double mass rating of 2 lb.m, in order to achieve the same 32 ft/s/s rate of
acceleration, the acceleration/Action
force impressed against Sphere 2 will have to be doubled to 2 lb.f. Then
Newton's formula, acceleration = Force / mass, will become acceleration = 64 P
/ 2 lb.m yielding the same
acceleration rate of 32 ft/s/s. These two events are a restatement of Newton's
LAW II where if the mass attribute of Sphere 2 is double that of Sphere 1 then
it will require double the
acceleration/Action force to cause Sphere 2 to accelerate at the same rate as
Sphere 1.

So you see, if we artificially adjust the cart's acceleration/Action force so
that this a/A force always remains proportional to the test object's mass
attribute (at the ratio in Poundal / lb.m of 32 /
1), then the same rate of acceleration will occur to each object tested. Thus a
10 lb acceleration/Action force applied to a 10 lb.m object will cause an
acceleration rate of 32 ft/s/s. Likewise, if a
160 lb a/A force is applied to a 160 lb.m object, the same 32 ft/s/s rate of
acceleration will be the result. Here then it is no mystery as to why in each
case the resulting acceleration rate remains
a constant 32 ft/s/s. All that is needed for acceleration to remain constant is
for the Force / mass ratio of each test event to remain constant.

Now I am ready to turn our attention from horizontal acceleration to vertical
acceleration being caused by each test object's internally generated force of
Earth gravitation. We already know
that each object at Earth's surface falls initially at the same rate of 32
ft/s/s. From the above test we also know that in order for the acceleration
rate of each object to remain at a constant 32
ft/s/s, the proportionality or ratio between the acceleration/Action force and
the object's mass attribute must also remain constant. For example, if a 1 lb.m
object loses its support at Earth's sea

level, a 1 lb or 32 Poundal a/A force is required to be impressed against or
within the object's matter to cause the object to accelerate toward Earth's
center of mass at the initial rate of 32 ft/s/s.
Since we know the 1 lb.m test object will freely bear against a scale with the
1 lb.f of its weight prior to losing the support of the scale, and further
since we know that a 1 lb.f converts to an
absolute 32 Poundal of force, we may conclude that the correct 32 / 1 ratio in
Poundal / mass exists resulting in the 32 ft/s/s rate of acceleration just as
predicted by Newton's formula, a = F / m.

If we double the mass of the test object to 2 lb.m, a measure of its weight
will indicate a 2 lb.f or 64 P. Again 64 P / 2 lb.m yields the same proportion
or ratio of 32 / 1. Again upon losing its
support this second test object will initially accelerate toward Earth's center
of mass at the same 32 ft/s/s rate as the first test object.

**Conclusion**

Given the same location on Earth, upon suddenly losing its support, each solid
object tested will initially begin falling at the same 32 ft/s/s rate of
acceleration simply due to the experimentally
provable fact that the acceleration/Action force of Earth gravitation being
generated within the matter of each object always remains proportional to the
object's quantity of matter (mass) at the
ratio in Poundal / lb.m of 32 / 1. Just as when we artificially adjusted the
a/A force during the horizontal acceleration events in order to keep the 32 / 1
force-to-mass ratio constant, each test
object's acceleration/Action force of Earth gravitation is automatically and
naturally adjusted according to the quantity of each object's matter (mass)
thereby keeping the force to mass ratio
constant at 32 / 1.

Thus the clue I gave to you early on in this answer was simply the statement of
Newton's formula, acceleration = Force / mass. This formula points the way to
Newton's LAW II and the simple
reason why all solid objects at a given location on Earth initially begin
falling at the same rate of acceleration.

Your friend in understanding the nature of Physics,

Ethan Skyler

April 5, 2002

P.S. Note that, as always, there is no role for Newton's imaginary inertia to
fill. (See Article I: The Reality of Newton's Inertia) Objects always fall at
the same rate due to the simple fact that the
gravitational force that is causing their acceleration always remains
proportional in magnitude to the quantity of the object's matter at the ratio
in Poundal / lb.m of 32 / 1.

Copyright © 2002 - 2015 by Ethan Skyler. All rights reserved.

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