We can all sense how far away things are.
There are lots of ways we perceive distance,
but a classic method we learn at a young age
is that things that are further away look smaller.
In this activity you and your children will explore
how size affects the way we perceive distance,
and use that knowledge to try and trick your own brains.
Our brains use visual information
like the size of objects to tell how far away things are.
A fun way to start investigating this
is to compare the size of a toy car held close to your eye,
with a real car across the street.
So they do look the same size, but are they?
No, this is teensy-weensy, and that one I can't do this to!
So just now, outside, we held up this small car against a car across the road.
How did the car across the road look, the real car?
Smaller than this car.
But which one is bigger?
That one!
And why did that one look smaller...
You can explore the idea further with a simple drawing activity.
So, what we're going to: You're going to grab a pencil,
and I'm going to draw a house here, you're going to draw a house over there.
Working together, draw two houses on a piece of paper.
I'm going to stick a rocket launcher on my house, aiming at your house...
By introducing some visual cues to these drawings,
you can start to experiment with your understanding
of how our brains process depth.
That's a good house!
Now we are going to draw a house from here to here using a ruler
to separate the landscape from the sky.
Do you know what we call that line?
Horizon?
Yeah!
Next, add the horizon:
A horizontal line that cuts across the image and separates the ground from the sky.
Just point to anywhere along the line there.
I'm going to put a little dot where you put your finger.
Now, that little dot is going to be the point that's so far away we can't see it.
Next add in the vanishing point.
This can be anywhere on the horizon line, between the two houses.
Draw lines from the corners of your houses going towards the vanishing point
to add in the side walls and give the drawing a 3D look.
Encourage the kids to think about how positioning and size
make things look near or far away on the drawing,
and how that�s similar to real life.
Whose house looks bigger?
Me, me me!
And why does your house look bigger?
Because it's closer to the end of the page and because I drew it bigger.
And what about mine?
Yours looks smaller because it's closer to the other end.
Whose house looks closer to the vanishing point?
I have a little LEGO man here and I'm going to put him right by the door of your house.
How does he look, in terms of size?
He looks small.
You can play around with your drawings by adding in toy people at different points.
What about if I put him next to my house here?
Your house looks tiny so he looks like a giant.
The toy people will look small in some parts of the drawing, and like giants in others,
because their size does not change relative to the drawing.
And we can take advantage of this idea in a simple illusion�
So now that we know that things that look further away look smaller,
we are going to use that to trick our brains.
We're gonna cut these out and build weird shaped room.
This 'weird-shaped room�, also known as an 'Ames room' is a false-perspective room.
A type of illusion that takes advantage of how our brains perceive depth.
Download the templates from rigb.org/experimental,
carefully construct the Ames room,
and take a look through the peephole to see it for yourself.
So have a look through that hole. How does it look?
Looks normal.
When our viewpoint is restricted like this,
all the angles and lines of the room line up in just the right way
to appear as normal shaped room.
But if you add in two objects of the same size, such as two toy people...
Do they still look the same size?
Oh my gosh! No!
Who looks bigger?
That one.
But those are the men we just had, but one of them looks...
smaller!
Why's that?
It's hard to explain, it looks like a straight house but it's actually not.
llusions like this boggle our brains.
While you�re doing your drawings and looking at the Ames room, ask lots of questions.
For example, ask your kids if they can work out how the illusino works to trick their
brains.
Me and Sahara had a great time today building this Ames room.
You can have a go yourself, just download the templates from the Ri website,
and send us pictures of your Ames room, we'd like to see them.
And don't forget to like and subscribe!