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What obvious adult discoveries made you feel a bit of a plonker?

687 replies

Airconfan · 21/09/2026 00:36

What’s something you learnt as an adult that made you think that’s completely obvious and yet I have never considered that….i feel like a bit of a plonker?

Mine was when taking tablets, the more you drink with it the better it will dissolve. I think alot of tablets are testing with the assumption people will drink 250ml alongside it.

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11
HappiestSleeping · 21/09/2026 07:19

Carolenarua · 21/09/2026 03:13

That the sun doesn't rise. Morto!!

Did you hear about the caveman who wanted to know where the sun went at night?

He decided to go and have a look, and was just going over a hill when it dawned on him.

Justforchristmas · 21/09/2026 07:20

Squirrelsnut · 21/09/2026 07:06

My dad, an intelligent and well-read person, somehow got to adulthood thinking that it was 'chimley' not chimney.

Chimley is a regional variation of chimney

GrannyAchingsShepherdsHut · 21/09/2026 07:21

On the subject of tablets - if you're taking pills, it works as expected to tip your head back to swallow. But if you're taking capsules, tip your head forwards instead - they float!

Squirrelsnut · 21/09/2026 07:22

Justforchristmas · 21/09/2026 07:20

Chimley is a regional variation of chimney

He was from Hull, born 1930, and had a strong 'old Hull' accent. I miss him.

PersephoneParlormaid · 21/09/2026 07:29

My dad always said chimley too, and he was a builder!

Seziah · 21/09/2026 07:33

My boyfriend recently found out that gherkins are just small cucumbers. He is 40

Mulledjuice · 21/09/2026 07:36

Carolenarua · 21/09/2026 03:13

That the sun doesn't rise. Morto!!

and nor does the tide!

ArcangelaTarabotti · 21/09/2026 07:36

Justforchristmas · 21/09/2026 07:20

Chimley is a regional variation of chimney

I think in Shakespeare’s time it was ‘chimbley’

LadyCurd · 21/09/2026 07:38

Seziah · 21/09/2026 07:33

My boyfriend recently found out that gherkins are just small cucumbers. He is 40

Erm I’m 45 and just found that out thanks to this post 🤣

Seziah · 21/09/2026 07:39

Very random but I recently found out that the phrase and movie “ex machina” is pronounced “ex makina” not “ex masheena”
(It means “from the machine”, from “Deus ex machina” (God from the machine) which now is used to mean a movie plot technique where something random or unexpected saves the day)

SoupSoup · 21/09/2026 07:48

Twokittenchaos · 21/09/2026 07:04

Washington D.C isn’t in Washington state. Not quite as practical as some of the above but still a bit of a “who knew!” age 30-odd. Apparently most people.

I knew it wasn’t in Washington state, but think I was in my 20s and living in the US before realising that Washington DC is so called because it isn’t in a state at all — it’s in an invented federal district under the jurisdiction of Congress, so as not to give any state the advantage of having the capital. Surrounded by Maryland and Virginia, but not in either.

Thrownunderthebuz · 21/09/2026 07:50

JeatherLacket · 21/09/2026 07:00

What is a UV light supper? And what is turning lights upside down?

Whatever this is is totally unknown to me even now I've read your post😁

Got to say I’ve loved glow in the dark stuff all my life. I think it started with an owl key ring.

Do you remember the glow by global T-shirts?We used to want them to glow as much as possible so we’d get mums bedside lamp and use it upside down to focus a beam of light and it made the t-shirt glow better.

I may have not described it well but I bought a UV LED usb strip light off Amazon approx £8 to use with UV reactive makeup. When showing the children I didn’t realise that one several pots had glow stars in them When we turned the light off. (We were in the dark) the stars glowed so strongly. Tested on other glow in the dark stuff watches and a pair of tights 😳 the UV light superchargers the items to glow effect.

Honestly can’t believe it

CrochetMadRosie · 21/09/2026 07:54

Squirrelsnut · 21/09/2026 07:06

My dad, an intelligent and well-read person, somehow got to adulthood thinking that it was 'chimley' not chimney.

This was me too…

At uni, in a teaching English lecture and the lecturer asked what mistake might children make when reading the word chimney.

I had my hand up ready to say that they might read it and say ‘chimNey’ when thank goodness she chose someone else who said that they might say ‘chimly’ because they’re over using the ly suffix!!!

I was mortified at what nearly happened!! My friend and I might have spent a proportion of the rest of the lecture laughing at what I nearly did though!Blush

Weekmindedfool · 21/09/2026 07:57

Thrownunderthebuz · 21/09/2026 03:17

Very low brow but only this weekend discovered that a UV light supper charges any glow in the dark item. It is plainly obvious now that the glow item absorbs UV.

Years of tuning lamps upside down to get stuff to glow better for the children and myself as a child solved with a £6 USB UV light.

Still can’t quite believe it 😳

How much glow stuff does one person have?

Weekmindedfool · 21/09/2026 07:59

Mulledjuice · 21/09/2026 07:36

and nor does the tide!

Well yes it does, by moving to shallower coast.

Isabella70 · 21/09/2026 08:01

GrannyAchingsShepherdsHut · 21/09/2026 07:21

On the subject of tablets - if you're taking pills, it works as expected to tip your head back to swallow. But if you're taking capsules, tip your head forwards instead - they float!

Actually maybe people can tell me - why do they tip their head back to swallow tablets? They don't do it with anything else they swallow.

I remember seeing a lecture by someone on, amongst other things, how swallowing works and he demonstrated the fact that gravity has nothing to do with it by standing on his head and drinking water.

stickygotstuck · 21/09/2026 08:04

Fizbosshoes · 21/09/2026 07:17

I was an adult when I found out silicon valley was related to tech, for years I thought it was related to plastic surgery Blush

The devil is in the detail: 'silicon' is not the same as 'silicone'.

I bet this is a common misunderstanding.

saveforthat · 21/09/2026 08:05

I've posted this before but I thought the channel tunnel was under the sea not under the sea bed.

Shedmistress · 21/09/2026 08:06

Thrownunderthebuz · 21/09/2026 03:17

Very low brow but only this weekend discovered that a UV light supper charges any glow in the dark item. It is plainly obvious now that the glow item absorbs UV.

Years of tuning lamps upside down to get stuff to glow better for the children and myself as a child solved with a £6 USB UV light.

Still can’t quite believe it 😳

You don't even need to do that. A flash from an old fashioned camera should recharge them.

ArcangelaTarabotti · 21/09/2026 08:07

saveforthat · 21/09/2026 08:05

I've posted this before but I thought the channel tunnel was under the sea not under the sea bed.

My children were disappointed when they first just went through as they were expecting to be in a glass tube and be able to see the fish😃

Shedmistress · 21/09/2026 08:08

Merrybandofpirates · 21/09/2026 07:15

I think she means using a UV light will “super charge” a glow in the dark item so it will be much brighter when in darkness.

And I assume she was turning lamps upside down because she thought a normal light bulb would “charge” them, so was trying to point the fat part of the lightbulb towards the glow in the dark item by turning the lamp upside down and pointing it at the thing? But I really don’t understand the logic behind that part. Lamps aren’t torches, she could have just sat them on the table underneath the lampshade if she thought a normal lightbulb would work.

Edited

They are usually on ceilings and walls, hence pointing the light up to them.

AbzMoz · 21/09/2026 08:09

ArcangelaTarabotti · 21/09/2026 08:07

My children were disappointed when they first just went through as they were expecting to be in a glass tube and be able to see the fish😃

I thought the Mersey tunnel’s roof was see-through, but I blame Willy Russell’s ‘Our Day Out.’

Shedmistress · 21/09/2026 08:13

Seziah · 21/09/2026 07:33

My boyfriend recently found out that gherkins are just small cucumbers. He is 40

Gherkins are not just small cucumbers, they are a type of cucumber bred for the ability to be small and not be too watery, as cucumbers go, so more suitable for long term pickled or fermented storage.

Isabella70 · 21/09/2026 08:13

saveforthat · 21/09/2026 08:05

I've posted this before but I thought the channel tunnel was under the sea not under the sea bed.

That's not unreasonable, some tunnels actually do lie on sea bed.

Releasemeplease · 21/09/2026 08:14

Bananavibez · 21/09/2026 03:19

That you dont rinse your mouth out after brushing your teeth

I'm in my 70s and I only learnt that last month!
I've brushed my teeth twice a day since a tiny child but I was never even shown how to use the toothbrush correctly. So my dental hygiene routine has been a learning curve all my life. The not rinsing came to light after the new hygienist I saw last month advised me to get a water flosser. When I bought it I was confused about where it fitted in to the tooth brushing, interdental brushes and mouth wash procedures. Google A1 provided me with a tooth cleaning regime which included the information about not rinsing after brushing and mouth wash should be used to freshen the mouth at mid day or similar tims in-between brushing. I'm still reeling from the shock.
Also fed up that tooth cleaning, boring at the best of times , is also now more complicated. On the plus side I've got all my own teeth and they are in decent nick.