On Sat, 15 Dec 2018 15:59:21 -0600, AMuzi wrote:

On 12/15/2018 3:04 PM, Emanuel Berg wrote:
Frank Krygowski wrote:

Emanuel, with all due respect, you should
spend the winter reading a physics book or
two. Or three. Skip the parts on electricity,
atomic physics, etc. Concentrate on forces,
motion, work, energy etc. - the parts that
apply to bicycles. [...]

Blah blah blah, you have told me this at least
a dozen times by now. Probably because it is
easier to be didactic/demeaning than to
actually answer the questions.


more.

I left school without having slept through even one physics
class. My reference work here is a 1955 high school textbook
for $1 (9 Kr). I don't know all of even that, but I
understand the world well enough to know that this headline
last week:

https://www.dailymail.co.uk/sciencet...soon-2022.html

was completely ridiculous. The chamber pressures are in the
same range, but not power, not even within a magnitude*!
Power is work over time. Without some grasp of the actual
world, you would not have laughed aloud when reading the
headline, etc.

*A typical 120mm tank round is 7.5 kilos of depleted uranium
moving at 1700 m/s. The new 6.8 rifle typically moves 7.5
grams at 850 m/s. That's why you need basic physics.


Interesting. First we argue that the old .30 cal was too big and heavy
so the 5.6 being lighter and faster is better and now we are saying
that the 6.8, although larger and heavier, is better. At this rate we
will be back to the 7.62mm :-)

What's next? A return to the 14.7mm?

cheers,

John B.