Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > sci.physics > #711429

Re: kilogram to be redefined

Show all headers | View raw

yporat08@gmail.com Wrote in message:

> > Double-AyesI think we can  take Planck constant as a basic physics constant is it practical*** for any evert day life ?? I wonder for a carpenter that  is  building a cupboard it is  not relevant ...     =============Y.P=============

For the primary etalons/standards, there is no need to be
 practical for everyday use. It  needs to be well defined,
 constant and  reproducible.

For everyday use, the derived secondary and lower level etalons
 and standards are made, based on practical technology like a
 wooden folding metre stick s.

Even in old days of Pt-Ir  metre etalons, no carpenter used it.
Neither later defined by krypton spectrum line wavelength, neither
 current  one defined by the light speed.

Similarly for  a second since 1/86400 part of day till the current
 multiple of tge caesium spectrum line period.


-- 
Libor Striz aka Poutnik ( a pilgrim/wanderer/wayfarer)

"Humour is the only effective weapon against stupidity."
Miloš Forman


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

Back to sci.physics | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

kilogram to be redefined Odd Bodkin <bodkinodd@gmail.com> - 2018-11-03 14:54 +0000
  Re: kilogram to be redefined benj <benj.fake@gmail.com> - 2018-11-03 13:26 -0400
    Re: kilogram to be redefined Odd Bodkin <bodkinodd@gmail.com> - 2018-11-03 18:07 +0000
    Re: kilogram to be redefined Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-03 20:29 +0100
      Re: kilogram to be redefined benj <benj.fake@gmail.com> - 2018-11-03 16:26 -0400
        Re: kilogram to be redefined Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-03 21:48 +0100
          Re: kilogram to be redefined Odd Bodkin <bodkinodd@gmail.com> - 2018-11-03 20:57 +0000
  Re: kilogram to be redefined Double-A <double-a3@hush.com> - 2018-11-03 16:01 -0700
    Re: kilogram to be redefined yporat08@gmail.com - 2018-11-04 00:46 -0700
      Re: kilogram to be redefined Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-04 09:00 +0100
  Re: kilogram to be redefined Steve <steve7600@gmail.com> - 2018-11-03 20:23 -0700
    Re: kilogram to be redefined Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-04 08:15 +0100
      Re: kilogram to be redefined Steve <steve7600@gmail.com> - 2018-11-04 01:11 -0700
        Re: kilogram to be redefined Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-04 09:35 +0100
          Re: kilogram to be redefined Steve <steve7600@gmail.com> - 2018-11-04 04:34 -0800
            Re: kilogram to be redefined Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-04 14:14 +0100
              Re: kilogram to be redefined Steve <steve7600@gmail.com> - 2018-11-04 19:52 -0800
                Re: kilogram to be redefined Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-05 06:58 +0100
                Re: kilogram to be redefined Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-05 07:37 +0100
                Re: kilogram to be redefined Steve <steve7600@gmail.com> - 2018-11-05 18:33 -0800
                Re: kilogram to be redefined Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-06 08:19 +0100
                Re: kilogram to be redefined Steve <steve7600@gmail.com> - 2018-11-05 18:44 -0800
                Re: kilogram to be redefined benj <benj.fake@gmail.com> - 2018-11-05 21:56 -0500
                Re: kilogram to be redefined Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-06 07:53 +0100
    Re: kilogram to be redefined yporat08@gmail.com - 2018-11-04 00:36 -0700
      Re: kilogram to be redefined Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-04 08:51 +0100
  Re: kilogram to be redefined Sergio <invalid@invalid.com> - 2018-11-05 14:41 -0600
    Re: kilogram to be redefined benj <benj.fake@gmail.com> - 2018-11-05 16:33 -0500
      Re: kilogram to be redefined Sergio <invalid@invalid.com> - 2018-11-05 23:38 -0600
        Re: kilogram to be redefined benj <benj.fake@gmail.com> - 2018-11-06 17:33 -0500

csiph-web