Do you automatically know how to convert the time to military hours?

[GoldenHours]

At work we always have to refer to military time/a 24 hour clock. I often see people having to count with their fingers to what the time is (e.g. counting that 8pm is 20:00). Similarly, with months I see people having to count with their fingers what number month it is when writing the date (e.g. counting to see that August is the 8th month).

Do you know the time in 24 hours and the number of the months off-by-heart or do you have to count it?

Yes, it's really quite basic - especially as watches & clocks tend to be digital, it's pretty standard, surely

@NiceGerbil

I cannot begin to get my head round doing physics/ maths in imperial.

Just... How?!

DP is not academic but he is a whizz at carpentry conversions. Wood usually comes in some multiples of feet or inches and he knows all of them in mm and will go off to buy an 8 X 4 board and go straight to the 2440 X 1220 mm one.

Same with drill bits and screws and has metric and imperial sets and knows which are equivalent or slightly bigger/smaller, as a socket that is half a mm too small is often useful for removing stuck bolts.

That's cool. I am shit at mental arithmetic!

I still have no idea how any system without a base - so X of this is that and y of that is the other. Can be used in physics without an awful lot of trouble!

@SquirryTheSquirrel

We have a right Mish mash that we get because we live here. But to outsiders it must be utterly confusing!

Yes, it would be interesting to know what metric/imperial anomalies exist in other countries. I have the (very possibly incorrect) impression that the USA is even more 'imperial' than we are, whereas continental Europe is firmly metric.

Harking back to Orwell again, he had someone in a pub in '1984' moaning that a half-litre of beer wasn't enough but a litre was too much - I find it interesting that in the 1940s a 100% metric future was seen as a given (or possibly a symbol of oppression). I suppose most alcohol is sold in metric volumes, it's just the pint of beer and associated measures that remain imperial.

As well as the UK and the US, only Liberia and Myanmar use miles on their road signs. I used that information during a lockdown zoom quiz.

Maybe George Orwell wrote about beer in litres because he had spent time in Spain?

But it does seem strange, because obviously at the time, the UK was fully imperial. I do find it amusing these days when products are sold in metric equivalents of pounds, pints etc, but scaled in the equivalent number of grams. Many things come in 454 or 908 g packs plus your big bottle of milk is 2.27 litres.

Very niche but physics related. Radioactive sources used in industry are almost always supplied in the unit used in the US, the Curie.

So the source will have an activity of 370 MBq, which is exactly 0.01 Curies, or something like 18.5 GBq.

You never get a 100 MBq or 50 kBq source for example, but always a multiple of 37.

I know the 24 hour clock but I still sometimes get it wrong, eg meaning to write 5 pm and putting 15:00.

I have to count through the months. When I write dates I put the month in letters (Jan, Feb, Mar, etc)

@BarbaraofSeville

Very niche but physics related. Radioactive sources used in industry are almost always supplied in the unit used in the US, the Curie.

So the source will have an activity of 370 MBq, which is exactly 0.01 Curies, or something like 18.5 GBq.

You never get a 100 MBq or 50 kBq source for example, but always a multiple of 37.

I did not know that! Which industries? Nuclear power/ hosp equipment/ ? I'll have to Google.

How does it work when those using the SI units try to get to grips with calcs etc?

That's just so weird!

Radiography uses millisieverts.

Nuclear submarines maybe? Military seem like the type to have traditions iyswim.

Millisieverts is a measurement of radiation dose to people.

Curies, Bq measures the amount of radioactive material.

Radioactive sources are used for process control in manufacturing, level and thickness measurements for sheet material production, eg paper.

Also industrial radiography, which examines welding integrity, exactly the same process as a hospital x-ray but more radiation.

I use 24hr time regularly as I used to work in the railway industry and it’s standard there.

My job involves constantly using, and calculating the time between dates, so I can fairly accurately work out the duration between any 2 dates in both work days (5d per week) and calendar days.

Each of the projects I work on has a set of dates associated with it that I can recall accurately, sometime years later.

I really, really struggle with currency exchange for some reason, I have A level maths and a very maths heavy engineering degree, but I just can never get my head around the conversions, I have to carry a post it note with me on holiday with £1 = x, £10 = y or I just get flummoxed..

UK graduates need to count on the fingers for the 24hr clock and don't know how dates work?
What are they graduating IN, fgs? My 7 year old doesn't need their fingers for either of those, and she's only just graduated from CP!

Ah that makes sense.. Thanks.

Does this have complications for h&s etc? This is fascinating!

Do you know why this convention persists?

I'm having a Google but the returns aren't much use!

Not especially problematic for health and safety as the activity of the source is only one factor and where possible it's locked in a shielded enclosure so most of safety is keeping people out of the enclosure unless the source is shielded in another way. Sometimes it is very much like the crystal maze if you remember that?

I think many industrial sources are made in the US, which would be one reason. Also it's an unintentional feminist issue as it's one of the few scientific units named after a woman so that's reason enough to me to keep using it.

As someone else mentioned, this is something learned in primary school. How anyone older than 7 can have issues with this is beyond me.

However, my ex was in the Navy and told me they'd had to change the entry tests because people were too stupid to understand the 24hr clock.

I did notice years back that bus timetables have a 'how to work out time in 24hr clock' section as all timetables use it.

Yes I do both without thinking about it.

I speak French and they use a 24h clock so that's second nature I guess. I prefer it to am and pm tbf as it can be quite confusing what time of day people mean if they don't specify.

Yes, and I always use the NATO phonetic alphabet if I need to spell something. (The proper one that is A-alpha not A -apple etc)

I use them automatically

I always refer to times using the 24 hour clock as I think it avoids any confusion and not having to add AM or PM is just more concise.
(I am irrationally irritated when I see e.g. 1300 PM as it’s totally unnecessary)

Doesn't it depend on how often you have to use 24 hour clock and numbers for months? I am old but remember having to check when younger. I hate people using the proper phonetic alphabet, because they usually reel it off dead quick and my brain can't keep up and they aren't words I hear day to day . It always feels like a power thing to me, or showing they've worked in particular roles . In my job I come across some not so nice people , often men do this.

@GoldenHours being dyslexic I always found telling the time in 24 hours easier rather than 12 hours - weird.

Judging by the shifts I’ve done in a vaccination clinic since winter a lot of people, particularly in their twenties and thirties, struggle with the 24-hour clock. Turning up at 4.30pm instead of 1430, etc. It’s been eye-opening.

I know both by heart

Military time 😂 24 hour clock is taught in primary, even my kids can do it. It's how I always say the time anyway

I'm a military brat so I know it all including the alphabet. But I thought most people did.