Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

[Phys-l] quote of the day



Here is an amusing passage:

The present does not seem to me to be an opportune time to enter
into the investigation of the cause of the acceleration of
natural motion(*), concerning which various philosophers have
produced various opinions, some of them reducing this to approach
to the center; others to the presence of successively less parts
of the medium remaining to be divided; and others to a certain
extrusion by the surrounding medium which, in rejoining itself
behind the moveable, goes pressing and continually pushing it
out. Such fantasies, and others like them, would have to be
examined and resolved, with little gain. For the present, it
suffices our Author that we understand him to want us to
investigate and demonstrate some attributes of a motion so
accelerated (whatever be the cause of its acceleration) that the
momenta of its speed go increasing, after its departure from rest,
in that simple ratio with which the continuation of time
increases, which is the same as to say that in equal times, equal
additions of speed are made.


*) Note: "natural motion" == free fall in a gravitational field.

=======================

If you don't recognize the passage, you can find the source easily
enough. Googling suffices.

And no, please don't tell me I'm making an appeal to authority. I am
not arguing the correctness of the passage based on who said it. The
ideas are important no matter who said them.

I will have more to say about these ideas tomorrow.