Radio Waves, Infra Red and Sound

Jan 22, 2007

—

On a number of occasions, I have tried to explain to Big about things like radio waves, radiant heat and so on.

Me: “It is like light but you can’t see it.”

Big (blank, puzzled, Daddy is taking the **** again look): “?”

We have talked about rainbows and splitting light up into different colours, that is fine, you can kind of see that and I think she has caught on to the idea that light can be bent.

Anyway, although I have had wondered about doing some digiscoping with our telescope, I had never considered whether digital cameras were any good at infra red. Well, it turns out that they are, in fact so good that the manufacturers have to go to great lengths to filter it out.

So if you want to prove the point, that there is light (emr) that you can’t see, try pointing a tv remote at a digital camera, or take a photo of the front of a Thinkpad like this one here (sorry, blurry, no tripod, no cable release, must buy myself a Gorillapod).

It’s where it is

Home Ed Inspiration, Ideas, and Activities

Click the links below and scroll through my collection of ideas, workshops, excursions, and more to discover practical everyday activities you can do together in and around your home classroom.

Home Education Inspiration

Home Ed: Ideas and Activities

Home Ed: Topics and Discussion

Exploring Neurodivergence in Children

Comments

13 responses to “Radio Waves, Infra Red and Sound”

Lin
22 January 2007
Not sure if its just me or not but I get nothing when clicking on the digiscoping link, a sham,e ‘cos I have no idea what it is! 😉
(May be me, we are having major bb probs here at the moment.)
Reply
Tim
22 January 2007
Sorry, should work now.
Reply
DaddyBean
22 January 2007
so what you gonna do about the rest of the Electromagnetic spectrum ?:-)
It’s quite a difficult one really, it’s one of those things were really you just have to accept that that’s the way the world is – kids at school much much older can struggle with it .
however, never thought of the digital camera thing, will ahev to have a play.
Reply
Tim
22 January 2007
Dunno, but I think it got across the idea that there might really be something beyond what you can see. I think she has already wondered how the tv remote worked, now she nows it is something ‘like’ light that does it, so it is not such a leap that it might be something ‘like’ light that accounts for the tv signal too. Maybe.
Reply
Jax
22 January 2007
You know, if you’d said it was like light you couldn’t see to me, you’d have got a blank look. Light is not dark, it’s what you see by. (Is it morning, is it light yet?) How can you have light you can’t see? If you’d said it was a colour you can’t make out you might have got further…we’ve already done things around rainbows – prisms breaking up light into different colours (though whether she remembers that) and colours recombining to make white on a little spinny thing, so colours might well have got you further.
Still think your experiment with the camera is rather fun though, I wouldn’t have ever thought of that.
Reply
DaddyBean
23 January 2007
Whereas i’d see talking about colours you can’t see just weird 🙂
SB seemed happy enough when we talked about UV ‘light’ the other day, in the context of vision and how cats see better in the dark, which wandered into things like some insects which can see UV light.
don’t know what she made of it though.
Reply
Tim
23 January 2007
I think the colours explanation makes sense, I wish I had thought of it, we will have to try it. 🙂
Reply
Raymond
23 January 2007
In the photo: is that the IrDA port you can see glowing (it’s not clear)? That’s neat-o! Must try it …
Reply
Raymond
23 January 2007
That’s brilliant! No.1 son has been asking about light and why things are different colours recently. I’ll show him this little demo later [I used my pocket digital cam and PDA].
Reply
Bob
23 January 2007
There was a documentary on BBC 4/2 last year (I think – might have been the year before) called Light Story. The DVD might be available – I seem to remember it was good and went on about the colours next to the visible spectrum as well as the visible stuff. (Plus some yuck stuff about Newton jabbing his eye with a pencil on purpose. Raving mad.)
Reply
Tim
23 January 2007
Raymond, sounds you have worked it out for yourself, yes, that is the IrDa port.
Reply
Tim
23 January 2007
Just crossed my mind, you could have a lot of fun with an IrDa hat and a CCTV camera.
Also, I am thinking of fitting my car number plates with IrDa. 🙂
Reply
Tim
23 January 2007
Just found this:
How to make a webcam work in infra red
Reply