Clock question

[Cybrvanr]

Here's a question that I posed to some of the people at work, and they couldn't figure it out at all. Some of the more technically inclined people however figured it out pretty quickly though:

You arrive home at 6 PM, and you notice that the power has been out at some point during the day. Your home is filled with a host of digital and analouge clocks. You notice that the analouge clocks are showing 5:30. The digital clocks are showing 8:15 AM. When did the power go out, and how long was it out for?

 

[Kevinpreston3]

The power was off for

30 minutes, 8 hours and 15 minutes ago.

The analogs powered back up after the power was returned. They show 5:30 when it is 6. They were off for 1/2 hour while real time continued ahead.

The electric clocks reset to 12:01 am, then started keeping time, winding around to 8:15am.

I may be wrong, I am SO tired right now!

 

[DADoES]

The outage occurred at 9:15 AM, for 30 minutes.

(that's assuming a few conditions)

 

[Kevinpreston3]

Yes, 8 hours and 15 mins ago

is when it resumed....zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz

 

[jasonl]

I have a GE kitchen clock from the 50s that keeps PERFECT time. It has a little window that tells if the power went out. If it's white, all is well, if it's red, the power went out.

Yay for old time clocks with smooth sweeping second hands.

Double yay for vintage KitKats

 

[toggleswitch]

I wonder how many of today's youth have even seen a corded electric wall-clock....

...and TRY to find one new

P.S. Jason my grandma had the same clock.

 

[Cybrvanr]

Looks like Kevin figured it out perfectly! I was amazed by the fact that many people couldn't figure this challenge out when I told it to some of the others I know!

 

[petek]

Me, I didn't even try.. arithmatic gives me a hives

 

[DADoES]

I am invisible.

 

[Kevinpreston3]

No you are not... Dadoes

YOu were more precise than me.

 

[kenmore1978]

eletric clock accuracy

"I have a GE kitchen clock from the 50s that keeps PERFECT time"
I once read somewhere that a corded electric clock should be accurate =/- 30 seconds. And yes does anybody still make large corded wall clocks? I know you can still buy corded bedside clocks

 

[petek]

Don't think anyones making corded ones now.

And they are hard to find considering the amount of thrifting I do everyday I've only come across one and I didn't take it because it it just didn't have any appeal, perhaps I should have. There were so many out there dunno where they've all gone. Thing is, there are plenty of kitchen clocks being made that even though they aren't vintage and run on batteries have great styling. I'm a clock nut btw, but prefer mechanicals or vintage electrics. I was so disappointed when as my 25th anniversary at work came I was given a nice looking Bulova mantle clock, opened up the back and there's that awful little plastic box with a AA battery inside. It holds no sentimental value to me at all and never will, all it reminds me of is how cheap everythings become.

 

[toggleswitch]

Austin and other memebers , pls correct me on this one...

It is my belief that the type of little electric motors in corded clock "count" the cycles in the altrenting curent and use that as a measure of time. Ususally the electric suppliers provide current that is nearly perfectly 60hz (or 50 hz).

Again, IMHO the only time it varies is when the grid is about to go down as during peak summer "stresses".

Again my understanding is that after major black-outs the time-consuming aspect of getting all the various generating stations back up-and-running is synchronizing the cycles. (Hertz).