|
|
> What universe do you live in? This is Road Runner Cartoon physics.
<snip from Paul's post>
With highly irregularly shaped objects one cannot use
the center-of-mass approximation. To get a (more) precise
answer, one would have to calculate the vectors of
gravitational acceleration caused by each molecule of
the irregular object individually and then add them all up.
<end snip from Paul's post>
so yes a massive object will be affect by gravity more
> Clearly, then, a man wearing a parachute falls at the same speed
> jumping out of an airplane regardless of whether the parachute opens
> or not, and the man would fall slower if he didn't use a parachute
> (which obviously weighs something) at all. So why were parachutes
> invented?
that is not what was said at all, but whatever. a parachute gives an object
a greater area for resistance to act upon, a steady resistance at that, this
is why a person with no parachute will hit the ground before a person with a
parachute, because the area exposed to resistance is much lower. it is also
why fat people... i mean big boned people... reach terminal velocity before
slimmer people, there is more area for air resistance to act upon.
parachutes are designed to give an object more area for resistance to act
upon, sky diving parachutes for example will give an area to counter balance
the effect of gravity on almost any object of almost any mass, if the mass
is not sufficient enough then the mass will get blown around. actually i
will restate that. parachutes are designed to give an object more resistance
almost irrespective of mass, which is exactly why there is extreme
deceleration when a parachute is opened allowing terminal velocity to be
much much lower than a free fall. if you ever bothered to read everything
you would have noticed that i have said many times over that the greater the
area of a mass exposed to a steady resistance, meaning the object is not
rotating in any fashion, the lower terminal velocity will be. acceleration
in a free fall remains a constant until terminal velocity is reached. i have
also said that objects will only fall at 9.8m/s/s in a complete vacuum where
there is no resistance acting on the mass note the penny and the feather in
a vacuum tube high school experiment. but in the real world only objects of
negligable mass AND negligable area for resistance to act on will fall at or
very close to 9.8m/s/s note the mythbusters penny from the observation floor
of the empire state building experiment. this is also dependant on the
viscousity of the medium the mass is falling through. a viscous medium will
provide a much higher resistance. an experiment you can do yourself is drop
a penny in a glass of water and a penny from an equal height through air,
both pennies have identical horizontal orientation, mass, and area, and see
which hits the ground (or bottom of the glass) first. to make it an even
more objective experiment, both pennies are heads up. there will be a small
yet delay between the penny dropped into the glass of water, and the panny
falling through air. conducting the experiment mentioned above will show you
that the only thing that affects the rate of free fall is the amount of
resistance, and how quickly resistance balances out mass.
|
|