0:00:05 > 0:00:08# If you've got a question and you don't know where to go
0:00:08 > 0:00:11# Ask Nina for some help cos she's got a science show
0:00:11 > 0:00:15# She makes sense of her senses while helping all her fans
0:00:15 > 0:00:18# By doing her experiments with potions and bangs
0:00:18 > 0:00:21- # Touch your tongue!- Tongue! - # Fingers!- Fingers!
0:00:21 > 0:00:23- # Eyes!- Eyes!- Ears!- Ears!- Nose!- Nose!
0:00:23 > 0:00:26# Nina and the Neurons find out what you need to
0:00:26 > 0:00:29# Nina and the Neurons find out what you need to know
0:00:29 > 0:00:33# Luke he helps us with our eyes, Felix with our touch
0:00:33 > 0:00:36# Ollie sniffs out smells and scents, Belle she hears so much
0:00:36 > 0:00:39# Bud is Ollie's brother, he helps us with taste
0:00:39 > 0:00:43# They're Nina's little Neurons they're coming to your place
0:00:43 > 0:00:46- # Touch your tongue!- Tongue! - Fingers!- Fingers!
0:00:46 > 0:00:48- # Eyes!- Eyes!- Ears!- Ears!- Nose!- Nose!
0:00:48 > 0:00:51# Nina and the Neurons find out what you need to know
0:00:51 > 0:00:54# Nina and the Neurons find out what you need to know
0:00:54 > 0:00:57# Oh, yeah! #
0:00:57 > 0:00:59- Ooh! - GIGGLES
0:00:59 > 0:01:01Come on, Nina. You can do it.
0:01:04 > 0:01:05Oh, hello there.
0:01:05 > 0:01:10I'm building a lovely big tower and I've only got two more cards to go.
0:01:10 > 0:01:12OK, OK.
0:01:12 > 0:01:14Concentrate, Nina.
0:01:19 > 0:01:20Ta-da!
0:01:20 > 0:01:23Oh, I am very pleased with that.
0:01:23 > 0:01:24COMPUTER BLEEPS
0:01:24 > 0:01:27Oh, I hear a beep, I see a flash.
0:01:27 > 0:01:29I wonder what they're going to ask.
0:01:33 > 0:01:35- BOTH:- Hi, Nina.
0:01:35 > 0:01:36Hi.
0:01:36 > 0:01:38We've got a question for you.
0:01:39 > 0:01:44Why do we see so many triangles in buildings?
0:01:44 > 0:01:46Oh, that's a great question.
0:01:46 > 0:01:49Why do we see so many triangles in buildings?
0:01:49 > 0:01:53Engineers often use triangles in buildings and structures,
0:01:53 > 0:01:54but I wonder why.
0:01:54 > 0:01:58Why don't you come down to my workshop and we'll investigate?
0:01:58 > 0:02:00- BOTH:- See you soon, Nina. Bye!
0:02:00 > 0:02:03Bye.
0:02:03 > 0:02:06Well, I'm going to need some help to answer this one
0:02:06 > 0:02:10and I know just who to ask. OK, Neurons, time to get to work.
0:02:25 > 0:02:28ALL: Neurons at the ready, Nina!
0:02:28 > 0:02:32OK, today's question is - why do we see so many triangles in buildings?
0:02:32 > 0:02:35Now, which Neuron do you think will be most useful
0:02:35 > 0:02:38in helping us find the answer?
0:02:38 > 0:02:40It's Luke!
0:02:40 > 0:02:42CHEERING
0:02:42 > 0:02:44NEURONS CHANT
0:02:48 > 0:02:52Cool, Nina. I'll be looking out to help you.
0:02:52 > 0:02:56Today's question is - why do we see so many triangles in buildings?
0:02:56 > 0:02:59Now, we'll be spotting lots of triangles,
0:02:59 > 0:03:01so Luke will be helping us today.
0:03:01 > 0:03:05But standby, Neurons, I've a feeling I may need help from all of you.
0:03:05 > 0:03:07Right, I need to get the workshop ready
0:03:07 > 0:03:11before the experimenters arrive.
0:03:11 > 0:03:13Grace loves pizza,
0:03:13 > 0:03:16Chloe loves going to the cinema,
0:03:16 > 0:03:21but they both want to know why do we see so many triangles in buildings?
0:03:21 > 0:03:23So, today, for one day only,
0:03:23 > 0:03:27Grace and Chloe become the experimenters.
0:03:32 > 0:03:35- Hi, guys. - BOTH:- Hi, Nina.
0:03:35 > 0:03:39Welcome to my workshop and thank you for your great question,
0:03:39 > 0:03:42"Why did we see so many triangles in buildings?"
0:03:42 > 0:03:46Well, let's start by having a closer look at this building.
0:03:46 > 0:03:48Now, what can you see?
0:03:48 > 0:03:51There are lots of triangles, Nina.
0:03:51 > 0:03:54You're right. So, this building is the Gherkin
0:03:54 > 0:03:58and not only does it have lots of small triangles,
0:03:58 > 0:04:03the small triangles make up bigger triangles.
0:04:03 > 0:04:07- But why do they use triangles, Nina? - Great question, Ollie.
0:04:07 > 0:04:10Well, let's start with an experiment.
0:04:10 > 0:04:14ALL: Whoop, whoop! An experiment! We're ready, Nina.
0:04:14 > 0:04:17So, we each have two different shapes.
0:04:17 > 0:04:18And what are they?
0:04:18 > 0:04:21- A square, Nina.- And a triangle.
0:04:21 > 0:04:25That's right. We've got a square and a triangle.
0:04:25 > 0:04:29So, can you lift your squares up for me? Like this.
0:04:29 > 0:04:33Now, let's give it a push on one side.
0:04:33 > 0:04:34Ooh!
0:04:36 > 0:04:40FELIX: Hmm. The squares are a little squashed.
0:04:40 > 0:04:41What's happened?
0:04:41 > 0:04:44- The square is squashed.- Yes.
0:04:44 > 0:04:49By pushing the square on one side, we've managed to change its shape.
0:04:49 > 0:04:54OK. Now, let's do the same thing, but with the triangles.
0:04:54 > 0:04:57OK, now let's give it a push.
0:04:57 > 0:04:59Oh. Hmm.
0:04:59 > 0:05:04- What's happening this time? - It didn't squash.
0:05:04 > 0:05:06Ooh, interesting.
0:05:06 > 0:05:12Well, let's try pushing the triangles in other directions, too.
0:05:13 > 0:05:14Hmm.
0:05:14 > 0:05:17LUKE: No, those triangles aren't changing.
0:05:17 > 0:05:21Yes! So, when a square is pushed...
0:05:22 > 0:05:26..the shape of the corners can change.
0:05:27 > 0:05:31But because a triangle has three sides,
0:05:31 > 0:05:34the corners can't change.
0:05:34 > 0:05:39So, triangles can be pushed on any side, in any direction,
0:05:39 > 0:05:41and they won't change shape.
0:05:41 > 0:05:43Triangles are very strong shapes,
0:05:43 > 0:05:47that's why engineers use them so often in buildings and structures.
0:05:47 > 0:05:49Can we make squares stronger, Nina?
0:05:49 > 0:05:51Great question, Belle.
0:05:51 > 0:05:55To find out, we're going to go somewhere really amazing.
0:05:55 > 0:05:57Let's go, experimenters!
0:06:03 > 0:06:06Hmm, where do you think we're going today?
0:06:06 > 0:06:08Nina said it was somewhere amazing.
0:06:08 > 0:06:10Maybe we're going to the jungle -
0:06:10 > 0:06:12that would be amazing.
0:06:12 > 0:06:15Will we see some crocodiles? Snap, snap, snap!
0:06:15 > 0:06:20Well, it's not the jungle, Neurons, but it does look amazing.
0:06:25 > 0:06:30So, your question was why do we see so many triangles in buildings?
0:06:30 > 0:06:34And, so far, we've found out that triangles are really strong shapes.
0:06:34 > 0:06:38But now we want to know if we can make square shapes stronger.
0:06:38 > 0:06:42So, I've brought you here to one of the world's most amazing structures,
0:06:42 > 0:06:45the Eiffel Tower in Paris.
0:06:45 > 0:06:48So, how would you describe the tower, experimenters?
0:06:48 > 0:06:51It's very, very tall, Nina.
0:06:51 > 0:06:54That's right, the Eiffel Tower is very tall
0:06:54 > 0:06:58and it needs to be really strong so that it doesn't bend in the wind,
0:06:58 > 0:07:01and so it's strong enough to hold up all of its weight.
0:07:01 > 0:07:04Now, we know that triangles are very strong,
0:07:04 > 0:07:06so let's see if there are any triangles
0:07:06 > 0:07:08in the Eiffel Tower. Let's go!
0:07:30 > 0:07:33Wow! This is the best tower ever!
0:07:38 > 0:07:42Yes, it's very nice. But we're a little high up, Nina.
0:07:44 > 0:07:48So, we've seen lots of triangles on our way up the Eiffel Tower.
0:07:48 > 0:07:50Let's have a closer look at these ones here.
0:07:50 > 0:07:55- Now, what do you notice about them? - They're inside squares, Nina.
0:07:55 > 0:07:58Yes, the squares have been turned into triangles,
0:07:58 > 0:08:00so let's do an experiment to find out why.
0:08:00 > 0:08:04These squares are just like the ones we used earlier.
0:08:04 > 0:08:07But I've added something. What do you think it is?
0:08:07 > 0:08:11- The middle bit.- Yes, I've added a piece of card across the middle
0:08:11 > 0:08:13to make this square into two triangles.
0:08:13 > 0:08:17Before, when we pushed the squares, they changed shape easily.
0:08:17 > 0:08:21So, let's see what happens if we try pushing these squares. Go for it!
0:08:21 > 0:08:25Cool, the squares aren't changing this time.
0:08:25 > 0:08:26What's happening?
0:08:26 > 0:08:28They're not squishing.
0:08:28 > 0:08:31That's right. Making the squares into triangles
0:08:31 > 0:08:34means the angles at the corners can't change.
0:08:34 > 0:08:37So the triangles have made the squares stronger?
0:08:37 > 0:08:39Yes, they have, Ollie.
0:08:39 > 0:08:44Turning a square into a triangle reinforces it, making it stronger.
0:08:44 > 0:08:50- Reinforces!- Reinforces means to make something stronger.
0:08:50 > 0:08:53And this square has been reinforced even more
0:08:53 > 0:08:56because there are two beams added to turn this square
0:08:56 > 0:08:59into four triangles, so it's really strong.
0:08:59 > 0:09:03And that's what the engineers who built the Eiffel Tower did, too.
0:09:03 > 0:09:08They turned the squares in the beams into lots and lots of triangles
0:09:08 > 0:09:09to make it really strong.
0:09:09 > 0:09:11Why are there so many triangles?
0:09:11 > 0:09:13That's a great question.
0:09:13 > 0:09:18Why are there so many? I think we need to get experimenting.
0:09:19 > 0:09:22Now, we can see the whole of the Eiffel Tower from here.
0:09:22 > 0:09:23What shape is it?
0:09:23 > 0:09:25A triangle, Nina.
0:09:25 > 0:09:28Yes, it looks like a huge triangle,
0:09:28 > 0:09:31but actually it's a shape we call a pyramid.
0:09:31 > 0:09:34Now, we are going to make our very own mini Eiffel Towers
0:09:34 > 0:09:36with some sticks and some sweets.
0:09:36 > 0:09:39Sweets? Did you mention sweets, Nina?
0:09:39 > 0:09:43Sorry, Bud. These sweets are for our experiment.
0:09:43 > 0:09:46Now, we're going to build one tower with a few big triangles
0:09:46 > 0:09:49and one tower with lots of smaller triangles.
0:09:49 > 0:09:51So, are you ready, experimenters?
0:09:51 > 0:09:53- BOTH:- Yeah!
0:09:53 > 0:09:54Let's get building.
0:10:08 > 0:10:10LUKE: Their towers are looking great.
0:10:11 > 0:10:14That's great work. We have two towers,
0:10:14 > 0:10:17but one has a lot more triangles.
0:10:17 > 0:10:21So, which one do you think will be stronger?
0:10:21 > 0:10:24This one? Well, we need to find out.
0:10:24 > 0:10:27So, we're going to add some weights to our towers, one at a time,
0:10:27 > 0:10:32and we'll balance them on the towers using these discs.
0:10:39 > 0:10:40Let's go.
0:10:41 > 0:10:43Gently...
0:10:47 > 0:10:49That's it.
0:10:49 > 0:10:51Good, OK.
0:10:51 > 0:10:55Oh! Fantastic, OK.
0:10:55 > 0:10:59Grace, you can add another weight onto yours.
0:10:59 > 0:11:02That's it, nice and gently.
0:11:04 > 0:11:07Great work, experimenters. So, stop there.
0:11:07 > 0:11:09So, Chloe, what happened to your tower?
0:11:09 > 0:11:11- It fell down, Nina.- Yes.
0:11:11 > 0:11:16The tower with a few big triangles squashed after two weights.
0:11:16 > 0:11:20Now, what about the tower with lots of small triangles?
0:11:20 > 0:11:22It's still standing.
0:11:22 > 0:11:26Yes, it has four weights on it, but it's not squashed at all.
0:11:26 > 0:11:31The tower built with lots of smaller triangles made a stronger tower
0:11:31 > 0:11:34and that's why the Eiffel Tower has so many triangles.
0:11:34 > 0:11:38The more triangles you have, the stronger your building will be.
0:11:38 > 0:11:41# Nina and the neurons. #
0:11:43 > 0:11:47So, your question was - why do we see so many triangles in buildings?
0:11:47 > 0:11:49And I think we've answered it.
0:11:49 > 0:11:53BELLE: Triangles are often used in buildings and structures.
0:11:53 > 0:11:58- BUD:- Triangles are strong shapes, they can be pushed in any direction.
0:11:58 > 0:12:02- FELIX:- But because their angles can't change, they don't change shape.
0:12:02 > 0:12:06OLLIE: Making squares into triangles reinforces them.
0:12:06 > 0:12:11- LUKE:- The more triangles you have, the stronger your building will be.
0:12:11 > 0:12:14So, I hope that's answered your question.
0:12:14 > 0:12:16- BOTH:- Thanks, Nina. Bye!
0:12:16 > 0:12:18Oh, you're welcome. Bye!
0:12:20 > 0:12:24If you want to know more about the science that's all around us,
0:12:24 > 0:12:27go to the Nina section of the CBeebies website. Have fun!
0:12:27 > 0:12:29# Superstructures
0:12:29 > 0:12:30# Superstructures
0:12:30 > 0:12:35# Superstructures, superstructures, superstructures
0:12:35 > 0:12:38# Some of them of tall, some of them are wide
0:12:38 > 0:12:43- # They're bumpy, lumpy, wiggly, too - Wiggly, too
0:12:43 > 0:12:45# Some of them are strong
0:12:45 > 0:12:47- #Some of them are small - Like me!
0:12:47 > 0:12:50# They're windy, whirly, whishy, too... #
0:12:50 > 0:12:51All around.
0:12:51 > 0:12:53Look over here!
0:12:53 > 0:12:57# Build it, stack it, pile it up
0:12:57 > 0:12:59# Come on, let's get building
0:12:59 > 0:13:01# Building, building, building!
0:13:01 > 0:13:05# Race it, hold it, make it stick
0:13:05 > 0:13:09# Come on, let's get building
0:13:09 > 0:13:12# Come on, let's get building
0:13:15 > 0:13:19# Some of them are cosy warm, some of them are chilly
0:13:19 > 0:13:23- # Keep us safe and hide us, too - Hide us, too
0:13:23 > 0:13:26# Some of them are just for fun or help us to stay dry
0:13:26 > 0:13:29# They're underground and high up too
0:13:29 > 0:13:31# Look around
0:13:31 > 0:13:33# Over here
0:13:33 > 0:13:37# Build it, stack it, pile it up
0:13:37 > 0:13:39# Come on, let's get building
0:13:39 > 0:13:41# Building, building, building
0:13:41 > 0:13:45# Race it, hold it, make it stick
0:13:45 > 0:13:49- # Come on, let's get building - Ooh-ooh
0:13:49 > 0:13:53# Come on, let's get building
0:13:53 > 0:13:54# Nina and the Neurons! #
0:13:54 > 0:13:58And remember, there are superstructures everywhere,
0:13:58 > 0:14:02whether they're big or small, wide or tall, we can all get building.
0:14:02 > 0:14:04See you again soon. Bye!
0:14:04 > 0:14:07- ALL: Bye! - Get building!