different frequencies as different colours. Or is it wavelengths?
Same difference. Higher frequency <=> shorter wavelength, it's a direct correlation.
Imagine a drummer hitting a drum at a consistent beat. The faster he hits it then the more beats per second you get (higher frequency) but the less time elapses between beats (shorter wavelength).
I’ve no idea how radios work.
A place I worked at years ago had a 1930s (IIRC) valve radio and a girl in the office was surprised to hear a current radio station playing on it - she assumed it would 'only be able to play old music'.
And yes, it's all EM radiation. How does radio work? The same way as light, Wi-Fi, 5G, microwaves, X-rays, TV remotes, sunburn, RADAR and a bunch of other shit. The only thing that really changes is the frequency / wavelength and the sensitivity of the receiving equipment (television, wireless card, eyeballs) to a given range within that spectrum.
I’ve no idea how radios work.
I like to imagine what the world would look like if someone could see radio waves as if they were light, but not see light.
It'd be sort of like a moonlit night, but there'd be a few really bright red lights on top of large towers around the countryside, and lots of smaller but bright blueish ones on top of buildings and lamp posts and stuff. And small lights like glowing LEDs all over your house. Your room would have pleasant blue mood lighting from the Wi-Fi router in the corner. People would be walking around with blue lights from their pockets as if they'd left the torch function on their phones on.
The weird part though would be that most things would look sort of like orangey clear perspex. You'd be able to see through your house and a few of your neighbours houses. But the wires and pipes and things would still be solid. In fact, even some parts of the landscape would have a dull red translucence.
Of course the colours would depend on what your radio-eyes could actually see as the difference between red and blue light is much less than the difference between FM radio waves and Wi-Fi or 5G.
A place I worked at years ago had a 1930s (IIRC) valve radio and a girl in the office was surprised to hear a current radio station playing on it – she assumed it would ‘only be able to play old music’.
I used to know someone who thought that if you held music cassette tape up to the light you would be able to see the notes and lyrics.
And yes, it’s all EM radiation. How does radio work? The same way as light, Wi-Fi, 5G, microwaves, X-rays, TV remotes, sunburn, RADAR and a bunch of other shit.
Well yes and no. That's like saying all substances are the same because they are all made of atoms - but drinking a glass of milk is not like drinking a glass of diesel.
Different parts of the EM spectrum interact with their surroundings and us in really quite different ways.
Yes, but would a pilot who thought a plane on a conveyor belt would take off be allowed to fly one?
Ben, step away from the LSD.
Well yes and no. That’s like saying all substances are the same because they are all made of atoms – but drinking a glass of milk is not like drinking a glass of diesel.
More yes though.. maybe a better analogy would be diesel, petrol, kerosene.. they're all hydrocarbons but with different numbers of carbons stuck together. EM radiation is just different frequencies/wavelengths from high/tiny (gamma radiation, x-rays) through visible then onto low/large (microwave, radio...).
I like to imagine what the world would look like if someone could see radio waves as if they were light, but not see light.
You'd need VERY big eyes to do that though! If a wavelength is metres / hundreds of metres..
IIRC some countries do insist on a minimal amount of mechanical knowledge as a part of the driving test - just basics like topping up fluids and tyres.
I am a person who needs to know the why and how before I can use something. I cannot learn by rote easily. thats a personality thing tho
Well yes and no.
I originally wrote at the end of that post, "note to Physicists, yes I know this is a gross oversimplification" but it got lost in editing somehow.
I am a person who needs to know the why and how before I can use something. I cannot learn by rote easily. thats a personality thing tho
Right?
This is one of the (many) concepts I tried to drum into the skulls of my apprentices. The difference it makes is that if you understand even loosely how something works then you're ahead of the game when you're presented with an issue that you've not seen before. You have the tools to work it out.
I once designed the front end “look and feel” of a bespoke online entry system – we knew it had to be idiot proof and simple and easy to read and (after a couple of fairly basic incarnations) it got to something that was genuinely very good and very capable.
Trouble with this is what seems idiot proof to you is not idiot proof to a proper idiot
We have this with computer systems at work. Fabulous complex databases that do all sorts of amazing things but you can tell that they were built by computer wizards with input from idiot users and that there was a huge comprehension gulf between them. I find navigating around it tricky for two reasons - its all TLAs and pictogrammes and unless I know what the TLA / pictogramme means ( and its not always obvious) then it just does not stick in my mind. the other reason is there are multiple ways to get to the same place - that confuses me and I am reasonably computer literate
Examples - the bit we use most is the EPR. what on earth is that? finally i found out its the Electronic patient Record the bit we called " the notes" when it was paper. "Notes" on the database is something very different. Or if i want to find the relatives phone number. Its a pictogramme of a stick person that when you hover over it says "demographics" so you have to click on that then into submenu for "other contacts"
My point being that what one person thinks is idiot proof really is not if you are not thinking in the same way
Ben, step away from the LSD.
If Ben is molgrips then I agree.
I had to explain to my 46 Year old girlfriend that only female cows have udders the other day.
I’m right aren’t I?
a degree qualified engineer i worked with thought that only bulls had horns (ie not cows). just wow
Try explaining the difference between a bull calf, a bullock and a bull
A place I worked at years ago had a 1930s (IIRC) valve radio and a girl in the office was surprised to hear a current radio station playing on it – she assumed it would ‘only be able to play old music’.
to be fair, with digital stations these days she'd be right.
to be fair, with digital stations these days she’d be right.
Yeah but this was around 1993 🙂
In very few other common areas of life would anyone proudly say “oh yes I’m hopeless at that!”. Cooking maybe? But even then most people at least know a few basic recipes they can get by on. Don’t they?
Can't cook to save my life but I'm not proud of it! It's basically due to me having a very limited diet due to allergies I had as a baby, thankfully I outgrew them! It means I have an involuntary stomach reflex to certain foods and tastes, makes me throw up spectacularly if I eat something like tomato. It's all mental as I no longe react to the foods, tomato for example made my throat close up, but my brain still goes "Nope!". Where it comes into cooking is I cannot taste a lot of stuff to see how it's going, meaning results are incredibly varied. I also have very little interest in food and it's taste due to not being to eat much while little so I don't have any interest in doing it. It causes issues with eating out, which I rarely do even in normal times, thankfully you can get pizza made without sauce!
Other things though I delve into how they work and my inquisitiveness can lead me down some proper rabbit holes, especially on YouTube!
Can you name the last 20 FA cup winners or all the Kardashian children, what about the hits of One Direction? I suspect there are many here who would happily declare their ignorance in these matters.
That's not really the same thing, that's general knowledge. It's not a "life skill" (other than perhaps not being able to answer a couple of pub quiz questions).
I can get through life knowing or not knowing that and it will make no difference whatsoever.
It's the knowing how things work from a user point of view (which is generally made as simple as possible) - like the earlier example, computers / the internet, certainly for the basics are generally very simple indeed. Kids can use a tablet, they're incredibly intuitive.
And then there's knowing how things work from a technical point of view but that is very different to the user point of view.
I couldn't tell you much about the inner workings of my computer other than I know the basic components and spec that it has. But I don't need to phone someone up and ask how to do online shopping!
I know why the Castle Bravo atomic test yield was almost three times that expected but I couldn't do the equations!
On the turntable thing, it's fun to put a record on and then lightly hold the edge of an A4 piece of paper in the groove. Amazes many folks
I remembered being told that if you drop a stone in a bucket the plop was air breaking the speed of sound but assumed I had remembered it wrong or Dad was taking the piss. I just Googled it and it turns out it is true. I claim the first thing humans made go supersonic was air from dropping stones into water
"According to one study, when a rock or other such object is dropped into water, an hourglass-shaped cavity of air is created, which then ejects the air at speeds faster than the speed of sound."
IIRC some countries do insist on a minimal amount of mechanical knowledge as a part of the driving test – just basics like topping up fluids and tyres.
You mean like England? As part of the driving test you have to answer a couple of basic questions about how to do just these kinds of tasks.
EM radiation is just different frequencies/wavelengths from high/tiny (gamma radiation, x-rays) through visible then onto low/large (microwave, radio…).
Right, but certain detection and interaction methods only really work with certain frequencies, so they are in effect different. You can't pick up light with a radio antenna can you?
Or can you? (goes off to Google..)
Thinking about it - metals are shiny because they reflect light, because the current induced in the surface of the metal causes a corresponding E and M field in the opposite direction. So why do radio waves not just bounce off antenna coils? It's to do with the wavelength of course and the size of the wires you'd need.. hmm
to be fair, with digital stations these days she’d be right
So how come on BBC Radio 3 on digital I can still listen to Bach?
There are more things that I don’t know how they work than things that I do know how they work.
but I know how to work google and books so it’s all good.
So how come on BBC Radio 3 on digital I can still listen to Bach?
Must be a recent recording?
Can’t cook to save my life but I’m not proud of it! ... I have an involuntary stomach reflex to certain foods and tastes,
I struggle with food in a similar fashion. But I love cooking. Weird, I know.
they reflect light, because the current induced in the surface of the metal causes a corresponding E and M field in the opposite direction
thinks… I didn't know that - but porcelain insulators are shiny too, so how does that work? Is reflecting the same as absorbing and re-emitting?
So why do radio waves not just bounce off antenna coils? It’s to do with the wavelength
So, a bit like the way near field earthquakes, being high frequency, shake things to bits, while far field earthquakes are long wavelength and just slosh lakes back and forth?
Former colleague didn't know bees eat honey. Not sure what he thought they made it for
Should've posted on here to ask the hive mind.
A friend from years ago thought that hens needed to have sex before they could lay an egg. He thought that battery hens were at it all the time!
Can recommend working through "Do you know?" with Maddie Moate on CBeebies. 200-odd explanations how things work and how things are made, with special cameras and animations even a small child can understand.
"Skyscraper and Flying Bird"
"Plant and Compost"
"Car Engine and Car Transporter"
"Day and Night and Solar Panel"
"Singing and Trombone"
"Bridges and Playground Flooring"
"Digger and Wellies"
"Cereal and Potato Harvester"
"Beehive and Mug"
"Digestion and Meringue"
"Clouds & Rain and Radiator"
"Metal Recycling Centre and Road Sign"
"Lighthouse and Bathbomb"
"Waves and Ice Cream"
"Library and Book"
"X-Ray and Sock"
"Tram and Map"
"Spider Web and Watering Can"
"Camera and Hairbrush"
"Sleep and Sofa"
but porcelain insulators are shiny too, so how does that work?
I would expect this is because they are glazed with a thin layer of transparent material on the outside. Because light can enter transparent materials but travels through them at a slower speed, you get refraction - and at suitable angles this leads to total internal reflection. You can get a good reflection off a piece of glass but only if you tilt it - however a piece of polished metal will give you a reflection at any angle.
So, a bit like the way near field earthquakes, being high frequency, shake things to bits, while far field earthquakes are long wavelength and just slosh lakes back and forth?
Yeah I suppose so. If you build a jenga tower on a tray, you can move the tray to and fro slowly and the tower stays up. But wobble it quickly, and it falls down. The movement of the tray is fundamentally the same, but different effects become dominant, with the end result that they are essentially different things. In physics, photons are both waves and particles at the same time, all the time, but they interact so differently with the surroundings that in certain situations they effectively ARE different things at different times.
I know someone who was going to the Isle of Man with a few friends, they had organised, she was just going along.
She was convinced that she was getting the ferry over from Leeds, and I was unable to persuade her that this was rather unlikely
I know someone who was going to the Isle of Man with a few friends, they had organised, she was just going along.......
I knew a very bright doctor who was going to the Isle of Wight for a holiday and was looking forward to driving around the TT race circuit.
I knew a very bright doctor who was going to the Isle of Wight for a holiday and was looking forward to driving around the TT race circuit.
And did they enjoy it?
https://www.goodwood.com/grr/race/modern/2020/7/introducing-the-isle-of-wight-tt/
