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Wrist Watch


Best Answer m00li, 12 May 2014 - 02:30 AM

Spoiler for still struggling
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11 replies to this topic

#1 TimeSpaceLightForce

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Posted 05 April 2014 - 05:19 PM

A strange wrist watch have it hands separated equally on 9:05:25 am..and seem to be working properly.

The second hand  runs at 1 rev per minute , the minute hand runs at 1 rev per hour while the hour hand runs 2 rev per day.

But everytime the hands overlaps they switch rotational speed.. Can you tell the rotational speeds of each hands when its

11:11:11 pm?


Edited by TimeSpaceLightForce, 05 April 2014 - 05:21 PM.

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#2 BMAD

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Posted 16 April 2014 - 06:58 PM

The rotation speeds change between any overlapping pair or when all three overlap?

Edited by BMAD, 16 April 2014 - 06:59 PM.

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#3 TimeSpaceLightForce

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Posted 17 April 2014 - 01:30 PM

The rotation speeds change between any overlapping pair or when all three overlap?

 Exchange is between any overlapping pair. When all three overlaps they also exchange rotational speed but not in random order.


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#4 bonanova

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Posted 17 April 2014 - 08:35 PM

But they always move forward?
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#5 HMGreatone

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Posted 18 April 2014 - 09:31 AM

At 11:11:11 PM, they are all standstill and not moving.


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#6 TimeSpaceLightForce

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Posted 18 April 2014 - 11:31 AM

@bonanova- yes they act like ordinary watches, you can tell the real time by knowing the 
fastest and slowest hands.
 
 
@HMG -Good point! and welcome here..
it is mechanical and automatic..the hands turn a certain angle every seconds. 
So it is still 11:11:11 until its 11:11:12 when all of the hands have moved.
 
Clue: Is 9:05:25 am same as 9:05:25 pm?

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#7 bonanova

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Posted 01 May 2014 - 05:13 AM

A strange wrist watch have it hands separated equally on 9:05:25 am..and seem to be working properly.

The second hand  runs at 1 rev per minute , the minute hand runs at 1 rev per hour while the hour hand runs 2 rev per day.

But everytime the hands overlaps they switch rotational speed.. Can you tell the rotational speeds of each hands when its

11:11:11 pm?

 

Does "when its 11:11:11 pm" refer to the actual time, or to the position of the hands?


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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#8 TimeSpaceLightForce

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Posted 01 May 2014 - 09:20 AM

 

A strange wrist watch have it hands separated equally on 9:05:25 am..and seem to be working properly.

The second hand  runs at 1 rev per minute , the minute hand runs at 1 rev per hour while the hour hand runs 2 rev per day.

But everytime the hands overlaps they switch rotational speed.. Can you tell the rotational speeds of each hands when its

11:11:11 pm?

 

Does "when its 11:11:11 pm" refer to the actual time, or to the position of the hands?

 

PM as in real time because when its 11:11:11 pm actual time, the 3 hands must be on "specific" angles..It can not be 2:56:11 or 11:11:10 or 2:10:56 actual time.
The hands' positions on 9:05:25am is same as 9:05:25pm (actual time) so the are actually around 2hrs,6min to figure this out..

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#9 m00li

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Posted 06 May 2014 - 06:29 AM

At 9:05:25 a regular wrist watch hands are at:

hr @ -87.291667 degrees

min @ 32.5 degrees

sec @ 150 degrees

 

therefore, a regular wristwatch cannot have its hands separated equally at 9:05:25. Hence, if a wristwatch has it hands separated equally at 9:05:25, it cannot be working properly. The question doesnt seem to be correct in stating BOTH "A strange wrist watch have it hands separated equally on 9:05:25 am." AND ".and seem to be working properly."


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#10 TimeSpaceLightForce

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Posted 08 May 2014 - 04:26 PM

At 9:05:25 a regular wrist watch hands are at:

hr @ -87.291667 degrees

min @ 32.5 degrees

sec @ 150 degrees

 

therefore, a regular wristwatch cannot have its hands separated equally at 9:05:25. Hence, if a wristwatch has it hands separated equally at 9:05:25, it cannot be working properly. The question doesnt seem to be correct in stating BOTH "A strange wrist watch have it hands separated equally on 9:05:25 am." AND ".and seem to be working properly."

  Good point! The solution for The Complex Clock Puzzle (Equal Separation of Hands) should not affect this one.
..the hands turn a certain angle every seconds. So it is still 9:05:25 until all of the hands have moved to a certain equality of angles..before 9:02:26 where the watch still seem
  (just looks like) to be working properly because the hands runs with proper speeds.
 
note: There is a pattern here ....

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