if a quarter and feather are dropped at the same time, will they hit
the ground at the same time?

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Request for Question Clarification by justaskscott-ga on 11 May 2005 18:39 PDT

Should we assume that they're dropping through the air to the ground
(as on Earth) or that there's no air between the objects and the
ground (as on the Moon)?

Either yes or no.  Take your pick.  Apparent simultaneity depends on
the frame of reference of the observer.

Forget the frame of reference stuff - I think it's outside the scope
of your question.  That idea deals with relativity, and only really
starts to take effect when you're dealing with objects travelling at
speeds on the order of the speed of light.

If the two objects are dropped in a vacuum, then they would be subject
to the same gravitational acceleration, and would hit the ground at
the same time.

If they are dropped outside from your balcony, aerydynamic forces will
prevent the feather from falling as fast as the quarter, so the
quarter will hit first.

An interesting experiment you can perform yourself at home:

Grab a large textbook and a piece of paper.  Drop them.  Normally, the
textboox will hit first and the paper will float down.  Now, place the
piece of paper on top of the textbook (some paper trimming may be
necessary).  Drop the book (with the piece of paper sitting on top of
it) and the paper will drop just as fast as the book.

Another thing you can do is to get a penny (mass ~ 1/400 lb) and
compare it to something like a bowling ball (mass ~ 10-15 lb).  Drop
them both from some height, and they will hit the ground at the same
time.

Yes the corect term to this Aerodynamic term thats causes the feather
to fall Slower than the quarter is called "Viscous Drag"

The Viscous Drag can be calculated by knoing the Dencity of the
medium, There gravatational force, and the height to fall. Kinetic
Energy is lost to the Viscous drag, hence the reason for of terminal
veolcitys,

The ammount of energy loss soely depends on the aero-hydrodynamics of
the object being droped.

Alex Peacock ( Mechanical Engineering Undergratuate BEng)

If they are dropped in a vacuum, they will fall at the same time
because the acceleration due to gravity is the same.
On Earth, the wind resistance will keep the feather from falling as
fast as the quarter.