Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: dentstudent on 20/01/2009 10:16:43
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I'm sure that I knew this, but have since forgotten. In my new pad, I can hear the village clock chiming away slices of the night every quarter of an hour [:(!], and so I've been able to lie awake and ponder this once more. So for the hour chime, which chime is the actual hour changing on? Is there international agreement about this, and so all clocks chime the hour on the same chime? For simplicity, it should be the first "bong", but it could also be the last.
[???]
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The "bong" is a rather ill defined time check but I have always found that the start of the first "bong" from 'Big Ben' most closely coinsides with the correct time whereas the start of the last 'Greenwich pip' is the correct time (nearly)
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Thanks Syphrum. Yes, it is ill-defined, but there must be a general concensus, wouldn't you think? Also, your Greenwich pips (post Gladys Knight, I assume) would be deviant through their broadcasting via radio. The 3rd pip was also the "stroke" used by the speaking clock.
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The first strike of Big Ben itself marks the time as you rightly say syhprum, not the preceeding Westminster chime, but on the 1/4 and 1/2 hour mark I'm not so sure.
It's enough to give you the pip!
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Hmm, interesting question that one.
Dedending on what 'bong' you refer too, time could even be perceived as being displaced.
Perhaps?
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Also, your Greenwich pips would be deviant through their broadcasting via radio.
I believe the 'Greenwich' pips are actually generated by an equipment rack somewhere at the BBC (but synchronised to atomic clocks). In the days of analog radio any delays would have been quite neglible, but in these days of digital processing - and certainly for digital broadcasts (DAB) and/or satellite broadcasts delays of a substantial fraction of a second are inevitable.