In article ,
Jaques d'Alltrades wrote:

Assuming I understand by your shorthand what you understand by it, you
still haven't addressed the 32ft/sec² element of the swinging ball.

As martin says, 'g'.

Air resistance is quite immaterial if you're measuring it how it *MUST*
be measured to comply with the law.

There is no legal requirement to measure it yourself, let alone one
to measure it in a particular way. If you measure it, and get less
that 10 foot-pounds or more than 14.5 with a 20% error (including
that due to air resistance), you can be pretty sure that an official
measuring would match the result of yours (i.e. legal or illegal).

Was it? The question I was addressing, and the one I expected you to be
addressing, was the measurement of muzzle-energy in foot pounds.

Er, yes. But, as every competent scientist and engineer knows, all
measurements have errors. A skilled one will measure something so
that the error is less than the difference between his measurement
and any point at which a decision changes (12 foot-pounds in this
case).

But estimating accuracy of measurements seems to me to be another phrase
approaching an oxymoron, and no, AFAIK the London syllabus didn't
include anything like it, except in passing.

The mind boggles! No, I will not continue this, er, debate - but
I can assure you that it is a standard and required activity by any
serious scientist or engineer.


Regards,
Nick Maclaren.

The message
from (Nick Maclaren) contains these words:

Air resistance is quite immaterial if you're measuring it how it *MUST*
be measured to comply with the law.

There is no legal requirement to measure it yourself, let alone one
to measure it in a particular way. If you measure it, and get less
that 10 foot-pounds or more than 14.5 with a 20% error (including
that due to air resistance), you can be pretty sure that an official
measuring would match the result of yours (i.e. legal or illegal).

Generic 'you'. If the ME is tested for the purposes of
legality/non-legality, it *MUST* be tested at the muzzle. (FSVO 'at')

Was it? The question I was addressing, and the one I expected you to be
addressing, was the measurement of muzzle-energy in foot pounds.

Er, yes. But, as every competent scientist and engineer knows, all
measurements have errors.

Not so, as any competent engineer/scientist will tell you.

A skilled one will measure something so
that the error is less than the difference between his measurement
and any point at which a decision changes (12 foot-pounds in this
case).

But estimating accuracy of measurements seems to me to be another phrase
approaching an oxymoron, and no, AFAIK the London syllabus didn't
include anything like it, except in passing.

The mind boggles! No, I will not continue this, er, debate - but
I can assure you that it is a standard and required activity by any
serious scientist or engineer.

Thank - er - goodness - for that.

--
Rusty
Open the creaking gate to make a horrid.squeak, then lower the foobar.
http://www.users.zetnet.co.uk/hi-fi/