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Riddle for the Castanauts.

Posted: Jul 9th, 2009, 12:27 pm
by Glacier
This actually happened. Can anyone guess why?

Sally in Prince Rupert gets up for work at the regular time on Monday.
She always shows up to work on
On Tuesday, she shows up for work more than 7 minutes early.
On Wednesday, she is over 14 minutes early for work.
Come Friday she is 36 minutes early for work.
Why?

Ask questions, and I will give clues.

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 12:45 pm
by Born_again
Was here clock a sundial, and the season was post winter solstice, but pre summer solstice?

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 12:55 pm
by Glacier
It has something to do with clocks and time. The clock used was a regular clock. BoB in Kelowna uses the exact same clock, but he got to work at the exact same time everyday.

Why would Sally's clock be off, while BoB's clock keeps the right time?

P.S. the names in the scenario have been changed to protect the innocent.

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 1:37 pm
by kgcayenne
Wasn't there some funky electricity thing going on up that end of the province this week?

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 1:52 pm
by Born_again
When you say "regular" clock, do you mean a mechanical clock, or an electronic clock that relies on the natural frequency of quartz to regulate the timing mechanism?

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 1:56 pm
by Glacier
I mean a cheap electric Walmart clock that plugs into the wall. Does it really use a quartz crystal, or does it use some other method to keep time?

kc, you are onto something...

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 2:28 pm
by Born_again
Was there a frequency shift of the domestically supplied AC current? For example, from 50Hz to 70Hz, or 50Hz to 40Hz?

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 2:37 pm
by Born_again
Ahhh! Was radio reception also effected, especially in the short wavelengths?

EDIT: Ok, my line of thought is that clocks and radios use quartz oscillators to regulate their 'timing'. The voltage applied to the quartz crystal will be relative to the vibration of the crystal. On cheaper electronic circuits without critical function, less is spent on ensuring that the crystals are protected from electro-magnetic influence(as well as temperature, shock, etc). It's my guess that they are encountering unusually high amounts of ionic radiation, which would be caused by the shifting of the earth's localised electro-magnetic fields -- in the same way that the aurora borealis becomes concentrated around the northern reaches.
Am I on the right track?

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 2:40 pm
by Glacier
No radio reception was effected, but the regular transmission line was down for maintenance leaving the Alcan and its respective transmission line to supply the area with power. Their power was running at 60.3 Hz instead of the the regular 60.0 Hz.

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 2:50 pm
by Born_again
Sorry, x-posted ^^

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 4:06 pm
by logicalview
Different clocks different times.

Problems with the space time continuum.

Actually it has nothing to do with the actual time.

It has more to do with her ability to show up at work at the prearranged time as agreed with her employer.

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 4:19 pm
by Glacier
Battery operated clocks are still keeping accurate time, but the ones you plug into wall receptacles are gaining time.

The question is, do you know how these types of clocks keep time?

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 4:43 pm
by I Think
LOL I think a friend of mine was doing the maintenance on the shut down line.

I would guess that lotsa clocks count the line frequency, was any equipment damaged by the shift.?

What happens when the out of phase electricity hits the in phase grid?

If one of the high voltage lines in a row of towers is even an inch longer than the others, a lot of heat is generated because it is now out of phase.

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 5:38 pm
by Born_again
I am convinced that her clock relies on AC line frequency to control the crystal frequency, and thus the timekeeping of the clock. You said that Alcan are supplying a 60.3Hz line frequency, so it is most likely the 0.3Hz difference that is doing it.
I recently had a bit of a problem on a barge where half of the generators were 50Hz(main supply) and the other half were 60Hz(for the 10 gigantic winch motors). The electrician had fitted a new PLC which controlled the operation of the sewage plant by committing various functions at various times. It turns out that the PLC was designed for 50Hz, so it was gaining about 10 minutes in the hour -- or 4 hours per day! This drove me batty because the plant was using too much dosing to maintain a healthy culture. We almost lost the whole culture, which would have meant a 2 week delay whilst the fresh culture establishes itself. In barge terms that's just under $5m!!

There you have it! I calculate that her clock gains 8 minutes per 24 hours at 60 + 0.3Hz
:nyah:

Re: Riddle for the Castanauts.

Posted: Jul 9th, 2009, 6:27 pm
by Glacier
Very good B_A :rate10:

Yes, almost all clocks do not have crystals, but instead rely on the frequency of the electricity supply to keep time. That 0.3 Hz change means the clocks are 0.5% faster than they should be, which adds up after a while.