![Thanks](https://www.renovateforums.com.au/dbtech/thanks/images/thanks.png)
![Likes](https://www.renovateforums.com.au/dbtech/thanks/images/likes.png)
![Needs Pictures](https://www.woodworkforums.com/images/smilies/happy/photo4.gif)
![Picture(s) thanks](https://www.ubeaut.biz/wave.gif)
Results 31 to 45 of 45
Thread: A Time puzzle to solve...
-
18th December 2023, 11:52 PM #31
Senior Member
- Join Date
- Nov 2017
- Location
- Melbourne
- Age
- 73
- Posts
- 108
Fair enough.
I'm sure you must be exhausted after this sort of precision answering your own general question about the position of the hands on an unspecified analog clock with an unspecified movement and commenting on the accuracy, deficiencies or otherwise of those who answered your problem.
Or could it be that it is impossible to identify the position of the hands on a non-quartz movement analog clock except by observation of a given clock because the machining and tensions and inter-operation of the various parts introduces unknown and incalculable variables which were not contemplated by the problem and formulas you posed?
No need to respond if you actually don't think you care or couldn't be fagged.
Just a bit of fun.
-
19th December 2023, 07:05 AM #32
Thank you FF for posting these maths related quizzes and taking the time to provide answers. It's got the grey matter working on logic and recall of high school maths which I'm grateful for. I hope you keep posting them when you have time.
And no need to begin with a long preamble about how this is an idealised situation and provide 25 caveats, it's implicit that it's the ideal case. Could you imagine an exam question written like that! Or how Einstein would have got around to explaining his theories of relativity if people piped up with 'wait, but is the train steam, electric or diesel, or my god, is it diesel-electric, and is there a nice restaurant car on it that serves a good BLT sandwich?' or 'is the rocket ship solid or liquid fuelled, does it have Netflix to make the time go faster?'
I see cheekiness in this post (the quartz clock) but also nastiness in the form of a Straw Man argument (the mechanics of a clock) designed to impugn the strength of your question, it's a compensation mechanism by those who couldn't or wouldn't solve it, much in the way a flash sports car is compensation for ED.
-
19th December 2023, 07:53 AM #33
SENIOR MEMBER
- Join Date
- Feb 2015
- Location
- Hobart
- Age
- 77
- Posts
- 190
All I can say is Thank God for digital timepieces !!!
I haven't got the time to figure out at what precise time one hand is over the over, at whatever hour...
As the piece's movement is continuous, I can only estimate that yours is a trick question!
For a milli-second there I thought I had the answer but the bloody thing moved again....
All I can say is we'll get to Xmas on the 25th.
Merry Christmas
Yvan
-
19th December 2023, 12:26 PM #34
Try not to be late, but never be early.
- Join Date
- Apr 2011
- Location
- Bakers Hill WA
- Age
- 76
- Posts
- 138
Reminds me of the time a policeman pulled me up and accused me of failing to stop at a stop sign. I explained to him the physics of an insect hitting your windscreen head on, in the split second between when the insect is flying forwards until it starts going backwards there is a moment when it is stationary, at this precise moment the vehicle is also stationary. Needless to say, the policeman was not impressed by my brilliant scientific knowledge and the ticket was duly written.
Cheers,
Geoff.
-
19th December 2023, 01:29 PM #35
"regular" in horological terms refers to the escapement mechanism invented by John Harrison around 300 years ago. The escapement mechanism allowed the spring spring tension to be released in a controlled manner so that the hands on a regulated clock always move at a constant speed regardless of the spring tension.
Horology is the study and measurement of time and the art of making of clocks and watches.regards from Alberta, Canada
ian
-
19th December 2023, 02:01 PM #36
Yes, I guess that makes John Harrison the father of "proper" navigation. You'd think they'd have the decency to call at Harrology wouldn't you?
-
19th December 2023, 02:09 PM #37regards from Alberta, Canada
ian
-
19th December 2023, 02:29 PM #38
The mundane Mondaine Clock position.
I am not going to consider:
- the time it takes M to accelerate and decelerate in its 6° travel in 1/16 second – it's unknown anyway
- anything to do with quartz
- wear and tear, age, quality, country of manufacture, the weight of any dust on the hands, wind direction, gravitational pull, La Niña effect or any other such ridiculous, pedantic notion to satisfy the 81st Prime Number
Assumptions:
- M starts moving at the very end of each 60 second period, rather than at 59 and 15/16 seconds (i.e. a 1/16 sec before the minute has finished).
- M and H are both symmetrical in their width shape, and are straight
Givens:
- We know that at 1:05 plus 1/16 seconds, M is at the 30° position, and that it only moves every 60 seconds.
- We know that at 1:06, M is still at the 30° position, but 1/16 second later it is at 36°.
- We know that at 1:05, H is at the 32.5° position, and that it advances at a rate of 0.5° per minute or 1/120° per second.
Thus, at 1:06:00, H has moved to 33.0°, and 1/16 seconds later it has moved 1/120/16° or 0.00052° (rounded) and will be at 33.00052°
So when will M be at 33.00052°?
A 1/16 second is 0.0625 seconds so it has to be a little over half of that time to move a little over half the distance (3.00052° of 6° travel)
So 3.00052 / 6 * 0.0625 = 0.03125542534 seconds
At 1:06 plus 0.03126 seconds to the nearest 1/10,000 sec is when the centre of M passes across the centre of H, or more realistically phrased as 1:06 plus 1/32 seconds (in other words plus half the 1/16 second it takes to click forward).
-
19th December 2023, 02:36 PM #39
-
19th December 2023, 02:45 PM #40
Agreed.
Also agreed. Real fun stuff, and completely uncalled for.
For clarity (definitions from internet search):
accurate adjective (especially of information, measurements, or predictions) correct in all details, exact
So giving rise to "as accurate as possible" if it can't be exact or precise, and not to be confused with
pedantic adjective excessively concerned with minor details or rules; over-scrupulous. Pointing out minor errors, correcting people who make small mistakes, and bragging about their own knowledge and expertise
-
19th December 2023, 02:46 PM #41
-
19th December 2023, 04:09 PM #42
I totally endorse Ian's recommendation. It was a major research project. Before that, coasts were discovered by running into them ... literally.
A major part of Cook's Endeavour voyage was trialling a chronometer. Did it work in practice as well as in theory? It did.
The French were also equally involved in similar research. On d'Entrecasteaux's voyages some 20 years later he carried 14 chronometers (# from memory). The Brits wanted to know if chronometers actually worked, the French wanted to know which was best! Science was advancing rapidly.
-
19th December 2023, 11:05 PM #43
.....at the third stroke the time will be..ah bugger.....at the fourth stroke the time will be..ah bugger.....at the fifth.... bugger it, lets have a beer instead
The person who never made a mistake never made anything
Cheers
Ray
-
19th December 2023, 11:14 PM #44
-
20th December 2023, 07:38 AM #45
SENIOR MEMBER
- Join Date
- Feb 2015
- Location
- Hobart
- Age
- 77
- Posts
- 190
Similar Threads
-
A mathematical puzzle to solve...
By FenceFurniture in forum NOTHING AT ALL TO DO WITH RENOVATIONReplies: 7Last Post: 11th December 2023, 12:35 AM -
Older women solve problems
By Allan at Wallan in forum JOKESReplies: 1Last Post: 15th September 2011, 06:49 PM