Re: Newton question

In article
<4a7043c1-b239-4e6b-9842-82117093b654@xxxxxxxxxxxxxxxxxxxxxxxxxxx>,
Efthimios <eangelopoulos@xxxxxxxxx> writes:

I will like some one to confirm my thinking to the following:

We know that:

1 Newton = kgr * m/sec^2

So if the force is not applied constant but periodicaly let say half
the time within a period, is the total force four times smaller (N/4)?

I think your question is based on a misunderstanding. While
mathematically correct, think of it as kgr * m/sec/sec. The sec^2
denotes an acceleration. Speed is m/s, and acceleration is change in
speed with time, or (m/s)/s. One can write this as m/sec^2 which will
not lead to wrong results, but one needs to think about what it means.

There are units like J/s/Hz. They are usually written that way, and it
is clear that it is one Joule per second per 1-Hz bandwidth. A Joule/s
is a watt, so one could also write W/Hz, which is fine. However, a
Joule is kg*m*m/sec/sec (a similar comment about m^2 applies similar to
that about s^2 above), and 1 Hz is 1/s, so one could write kg*m*m/sec.
Mathematically equivalent, but it disguises what is meant and why one
needs such a unit in the first place. Of course, directly it is
difficult to think of what kg*m*m/sec could possibly mean.

.