Leo Lichtman said:
<[email hidden]> wrote: (clip) Anyway, the object will hit the
pavement at the same speed as the same object toppling sideways from the
same height.(clip) (Stated as a conjecture, not as a fact.)
^^^^^^^^^^^^^^^^
Carl, there is a classic equality about falling objects which I think has
been distorted into this incorrect form.
A cannonball dropped from a given height will reach the ground at the same
time as a cannonball fired horizontally at the same time. Both will reach
the ground with the same vertical component. Both cannonballs will be
equidistant from the ground at all times.
This is equivalent to stating that the gravitational effect on the
cannonball is not related to any horizontal forces that are applied to it.
(With all the usual disclaimers about air friction.)
Dear Leo,
As Joe Riel's explanation makes clear, a beam rotating
around a pivot is not the same as a free-dropping
cannonball.
That is, a beam toppling sideways is not the same as
motionless beam released to drop straight down or a beam
fired horizontally out a cannon (which begins to drop at the
same rate).
Have a look at the cup and ball demonstration (the bottom
pictures) and its details:
http://www.physics.umd.edu/lecdem/outreach/QOTW/arch3/a043.htm
A beam of the right length at the right angle with a cup
near its end will pivot and fall faster than a ball when
both are released at the same time--the cup beats the ball
in the race to the table-top and catches it.
In contrast, a ball dropped from the edge of the table at
the same time as a ball shoots horizontally off the edge of
the table will reach the ground at the same time.
Carl Fogel
