Measuring Up
The following question appeared in a physics degree exam at the University of
Copenhagen:
"Describe how to determine the height of a skyscraper with a barometer."
One enterprising student replied: "You tie a long piece of string to the neck of
the barometer, then lower the barometer from the roof of the skyscraper to the
ground. The length of the string plus the length of the barometer will equal
the height of the building."
This highly original answer so incensed the examiner that the student was failed
immediately. The student appealed, on the grounds that his answer was
indisputably correct, and the university appointed an independent arbiter to
decide the case.
The arbiter judged that the answer was indeed correct, but did not display any
noticeable knowledge of physics; to resolve the problem it was decided to call
the student in and allow him six minutes in which to verbally provide an answer
which showed at least a minimal familiarity with the basic principles of
physics.
For five minutes the student sat in silence, forehead creased in thought. The
arbiter reminded him that time was running out, to which the student replied
that he had several extremely relevant answers, but couldn't make up his mind
which to use.
On being advised to hurry up the student replied as follows:
"One, you could take the barometer up to the roof of the skyscraper, drop it
over the edge, and measure the time it takes to reach the ground. The height of
the building can then be worked out from the formula H =3D 1/2gt squared (height
equals half times gravity time squared). But bad luck on the barometer.
"Two, if the sun is shining you could measure the height of the barometer, then
set it on end and measure the length of its shadow.
Then you measure the length of the skyscraper's shadow, and thereafter it is a
simple matter of proportional arithmetic to work out the height of the
skyscraper.
"Three, if you wanted to be highly scientific about it, you could tie a short
piece of string to the barometer and swing it like a pendulum, first at ground
level and then on the roof of the skyscraper. The height is worked out by the
difference in the gravitational restoring force (T = 3D 2 pi sqr root of l over
g).
"Four, if the skyscraper has an outside emergency staircase, it would be easy to
walk up it and mark off the height of the skyscraper in barometer lengths, then
add them up.
"Five, if you merely wanted to be boring and orthodox about it, of course, you
could use the barometer to measure air pressure on the roof of the skyscraper,
compare it with standard air pressure on the ground, and convert the difference
in millibars into feet to give the height of the building.
"Six, since we are constantly being exhorted to exercise independence of mind
and apply scientific methods, undoubtedly the best way would be to knock on the
janitor's door and say to him 'I will give you this nice new barometer, if you
will tell me the height of this skyscraper.'"
The arbiter regraded the student with an 'A.'
[ Author unknown  from Tim Davis ]
Inspirational Humor
SkyWriting.Net
All Rights Reserved.
