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 Because she's got a science show
0:00:11 > 0:00:15# She makes sense of our senses While helping all her fans
0:00:15 > 0:00:17# By doing her experiments With potions and with bangs
0:00:17 > 0:00:19- # Touch your tongue - Tongue
0:00:19 > 0:00:20- # Fingers - Fingers
0:00:20 > 0:00:21- # Eyes - Eyes
0:00:21 > 0:00:22- # Ears - Ears
0:00:22 > 0:00:23- # Nose - Nose
0:00:23 > 0:00:26# Nina and the Neurons Find out what you need to know, yeah!
0:00:26 > 0:00:29# Nina and the Neurons Find out what you need to know
0:00:29 > 0:00:32# Luke he helps us with our eyes And Felix with our touch
0:00:32 > 0:00:35# Ollie sniffs out smells and scents And Belle she hears so much
0:00:35 > 0:00:38# Bud is Ollie's brother He helps us with our taste
0:00:38 > 0:00:41# They're Nina's little Neurons And they're coming to your place
0:00:41 > 0:00:43- # Touch your tongue - Tongue
0:00:43 > 0:00:44- # Fingers - Fingers
0:00:44 > 0:00:45- # Eyes - Eyes
0:00:45 > 0:00:46- # Ears - Ears
0:00:46 > 0:00:48- # Nose - Nose
0:00:48 > 0:00:51# Nina and the Neurons Find out what you need to know, yeah!
0:00:51 > 0:00:53# Nina and the Neurons Find out what you need to know
0:00:53 > 0:00:55# Oh, yeah! #
0:00:56 > 0:00:59Doo-doo-doo. Oh, hello there.
0:00:59 > 0:01:03You just caught me making a balloon arch and I'm nearly finished.
0:01:03 > 0:01:05Ah-ha, that should do it. Ta-da! Ha-ha!
0:01:05 > 0:01:08Looks a bit like a rainbow, doesn't it?
0:01:08 > 0:01:10BEEPING
0:01:10 > 0:01:14I hear a beep, I see a flash. I wonder what they're going to ask.
0:01:18 > 0:01:20BOTH: Hi, Nina!
0:01:20 > 0:01:21Hi!
0:01:21 > 0:01:24We've got a question for you.
0:01:24 > 0:01:27Why do people use arches in buildings?
0:01:27 > 0:01:31That's a great question! Why do people use arches in buildings?
0:01:31 > 0:01:34I've just been making a beautiful arch out of some balloons
0:01:34 > 0:01:38but I'm sure the arches in buildings are much stronger.
0:01:38 > 0:01:41Come down to my workshop and we'll investigate.
0:01:41 > 0:01:43BOTH: See you soon, Nina. Bye!
0:01:43 > 0:01:45Bye!
0:01:45 > 0:01:48Well, I'm going to need some help to answer this one
0:01:48 > 0:01:50and I know just who to ask.
0:01:50 > 0:01:52OK, Neurons, time to get to work.
0:02:08 > 0:02:11ALL: Neurons at the ready, Nina.
0:02:11 > 0:02:15OK, today's question is, why do people use arches in buildings?
0:02:15 > 0:02:18Which Neuron do you think will be most useful
0:02:18 > 0:02:20in helping us find the answer?
0:02:20 > 0:02:22It's Luke!
0:02:22 > 0:02:23CHEERING
0:02:23 > 0:02:26ALL: Go, Luke! Go, Luke! Go, Luke!
0:02:26 > 0:02:30Go, Luke! Go, Luke! Go, Luke! Go, Luke!
0:02:30 > 0:02:34Cool, Nina! I'll be looking out to help you.
0:02:34 > 0:02:38Today's question is, why do people use arches in buildings?
0:02:38 > 0:02:40And because we see beautiful arches,
0:02:40 > 0:02:42Luke will be helping us today.
0:02:42 > 0:02:46Stand by, Neurons, I've a feeling I may need help from all of you.
0:02:46 > 0:02:50I need to get the workshop ready before the experimenters arrive.
0:02:52 > 0:02:54Phoebe likes eating chocolate cake.
0:02:54 > 0:02:58Dylan loves reading books about dinosaurs.
0:02:58 > 0:03:03But they both want to know, why do people use arches in buildings?
0:03:03 > 0:03:08So today, for one day only, Phoebe and Dylan become the experimenters!
0:03:13 > 0:03:16- Hi, guys!- BOTH: Hi, Nina!
0:03:16 > 0:03:20Welcome to my workshop and thank you for your great question,
0:03:20 > 0:03:22why do people use arches in buildings?
0:03:22 > 0:03:26Well, let's start by having a look at an arch.
0:03:26 > 0:03:29So an arch is a curved shape.
0:03:29 > 0:03:32Where have you seen arches in buildings before?
0:03:32 > 0:03:36- Under bridges.- Holding up roofs.
0:03:36 > 0:03:40Yes, we often see arches under bridges, like this one here,
0:03:40 > 0:03:44or supporting big roofs, like this one here.
0:03:44 > 0:03:49So people have been using arches to hold up buildings for a long time.
0:03:49 > 0:03:51In fact, have a look over here,
0:03:51 > 0:03:56these arches were built many, many years ago
0:03:56 > 0:03:58and they're still standing today.
0:03:58 > 0:04:01But why do people use arches in buildings?
0:04:01 > 0:04:03Let's do an experiment to find out.
0:04:03 > 0:04:06ALL: Whoop-whoop! An experiment!
0:04:06 > 0:04:07We're ready, Nina!
0:04:07 > 0:04:10OK, we're going to see how well
0:04:10 > 0:04:12this flat piece of card
0:04:12 > 0:04:15can hold up this heavy block.
0:04:15 > 0:04:17OK, Dylan, you pop the heavy block onto
0:04:17 > 0:04:19the middle of the paper for me
0:04:19 > 0:04:21and we'll see what happens.
0:04:21 > 0:04:24- What happened?- It got squashed.
0:04:24 > 0:04:27The flat card flopped, Nina.
0:04:27 > 0:04:30That's right. The heavy block pushed down onto the flat card
0:04:30 > 0:04:33but it wasn't strong enough to hold it up.
0:04:33 > 0:04:37OK, well, let's change the shape of the card into an arch
0:04:37 > 0:04:40and see what happens.
0:04:41 > 0:04:43I'll do it like this.
0:04:46 > 0:04:50Okey doke. Phoebe, if you can just pop the block onto the middle
0:04:50 > 0:04:53of the arch for me again. Let's see what happens.
0:04:53 > 0:04:56Oh, oh! Hee-hee-hee!
0:04:56 > 0:04:58Wow! Look at that.
0:04:58 > 0:05:03- So what happened this time? - It stayed up!- It did!
0:05:03 > 0:05:07So changing the shape of the card into an arch means that it can
0:05:07 > 0:05:11easily hold up the heavy block, even though it's the same
0:05:11 > 0:05:15piece of card that got squashed when it was flat.
0:05:15 > 0:05:19So the heavy block is pushing down on the arch
0:05:19 > 0:05:21and the pushing force goes down
0:05:21 > 0:05:24through the arch into the ground.
0:05:24 > 0:05:26Because the ground doesn't move,
0:05:26 > 0:05:29it helps the arch to hold up the block.
0:05:29 > 0:05:32So arches are really strong shapes
0:05:32 > 0:05:36and that's why they're used to hold up bridges and big roofs.
0:05:36 > 0:05:38What are those for?
0:05:38 > 0:05:40That's a great question!
0:05:40 > 0:05:42Those blocks are really important
0:05:42 > 0:05:44so I think we need to go somewhere
0:05:44 > 0:05:47with lots of curves to find out more.
0:05:49 > 0:05:54- LUKE:- 'Here we go! I can't wait to see where we'll end up today.'
0:05:54 > 0:05:56Nina said it would have lots of curves.
0:05:56 > 0:05:59Curves?! Like a banana!
0:05:59 > 0:06:01Maybe it's a banana factory!
0:06:01 > 0:06:04Ha-ha! Bananas grow on plants, Bud.
0:06:04 > 0:06:06Well, I can't see any bananas here
0:06:06 > 0:06:09but there are lots of curves.
0:06:10 > 0:06:13So far we've discovered that arches are strong shapes that can
0:06:13 > 0:06:16hold up heavy weights and we've come
0:06:16 > 0:06:18somewhere where there are lots of arches.
0:06:18 > 0:06:22Now, can you guess what's on top of those arches?
0:06:22 > 0:06:25- A train track!- Yes, a train track!
0:06:25 > 0:06:28Actually, I think there's a train coming now.
0:06:28 > 0:06:31- Shall we give them a wave?- Yeah!
0:06:31 > 0:06:33HORN HONKS
0:06:33 > 0:06:36Chugga-chugga, chugga-chugga. Whoop-whoop!
0:06:36 > 0:06:39Have a good journey!
0:06:39 > 0:06:40Ha-ha!
0:06:40 > 0:06:45So these arches need to be really strong to hold up a heavy train.
0:06:45 > 0:06:49Now, you had asked what the blocks at the side of the arches are for.
0:06:49 > 0:06:52So let's do an experiment to find out!
0:06:52 > 0:06:55So here we have some boxes of sand
0:06:55 > 0:06:57and I've made an arch in-between them.
0:06:57 > 0:07:02Now, let's see if the arch can hold up this toy train.
0:07:02 > 0:07:04Phoebe, try putting the train on top of the arch
0:07:04 > 0:07:06and we'll see what happens.
0:07:09 > 0:07:12Oh! Ho-ho-ho-ho! What happened?
0:07:12 > 0:07:15The train squashed it down.
0:07:15 > 0:07:17And the boxes moved.
0:07:17 > 0:07:20Yes, when you put the heavy train on top of the arch,
0:07:20 > 0:07:24the pushing force pushed the sides of the arch down and out
0:07:24 > 0:07:29and the boxes moved and the arch didn't keep its shape.
0:07:29 > 0:07:33Ha-ha! It was squashed flat like a pancake, Nina!
0:07:33 > 0:07:35That's right, Bud!
0:07:35 > 0:07:38Can you think of anything we could do to help the arch
0:07:38 > 0:07:40keep its shape?
0:07:40 > 0:07:42Make the boxes heavier.
0:07:42 > 0:07:46Hey, that's a great idea because if the boxes are heavier,
0:07:46 > 0:07:48they should be harder to move.
0:07:48 > 0:07:51Oh, and I just happen to have some rocks here,
0:07:51 > 0:07:54so let's put them in the boxes. Get some stones!
0:07:54 > 0:07:59Grab a couple of stones each. Come on, Dylan. Let's go!
0:08:14 > 0:08:17Now, guys, do you think the boxes are heavier?
0:08:17 > 0:08:19BOTH: Yes.
0:08:19 > 0:08:21Dylan, do you want to put the toy train
0:08:21 > 0:08:25back on top of the arch and we'll see what happens?
0:08:25 > 0:08:28Whoo! Ho-ho-ho-ho!
0:08:28 > 0:08:30Excellent work, experimenters!
0:08:30 > 0:08:35The heavier blocks at the side are helping the arch keep its shape
0:08:35 > 0:08:37and holding up the train.
0:08:37 > 0:08:41Real arches have heavy blocks at the side just like this, too.
0:08:41 > 0:08:43They're called buttresses.
0:08:43 > 0:08:47BUD-resses! Bud, that's me!
0:08:47 > 0:08:51No! It's buttresses, Bud! Hee-hee-hee!
0:08:51 > 0:08:53That's right, buttresses.
0:08:53 > 0:08:57Buttresses are heavy blocks that hold the arch firmly in place
0:08:57 > 0:08:59so it keeps its shape.
0:08:59 > 0:09:02What can you see at the end of the bridge?
0:09:02 > 0:09:04Big stones.
0:09:04 > 0:09:07That is the buttress and there's one at the other end too.
0:09:07 > 0:09:11Stone buttresses are really heavy so they won't move.
0:09:11 > 0:09:15They help hold all the arches together and keep the bridge up.
0:09:15 > 0:09:18Now, can you spot what the bridge is made from?
0:09:18 > 0:09:20Stones, Nina.
0:09:20 > 0:09:24Yes, stone. Now, is stone hard or soft?
0:09:24 > 0:09:26- Hard.- Yes, they are hard.
0:09:26 > 0:09:30And that's important too, so let's go back to the workshop
0:09:30 > 0:09:33to find out more.
0:09:33 > 0:09:35Now we want to know why arches are made out of
0:09:35 > 0:09:38hard materials like stone.
0:09:38 > 0:09:42And we are going to find out by building our very own arch.
0:09:42 > 0:09:44So we've got some building blocks here
0:09:44 > 0:09:49- and what do these things remind you of?- Buttresses.- That's right!
0:09:49 > 0:09:50Well-remembered!
0:09:50 > 0:09:52So we've got our buttresses,
0:09:52 > 0:09:55so we just need to build an arch between them.
0:09:55 > 0:09:57So, let's get building!
0:09:57 > 0:10:01Phoebe, do you want to come round here and help me with this one?
0:10:01 > 0:10:03OK.
0:10:03 > 0:10:09All right, Dylan, that's it. You get yourself into a comfy position.
0:10:09 > 0:10:12Excellent work, Dylan.
0:10:13 > 0:10:17Here we go! OK, that's it.
0:10:19 > 0:10:21Well done, experimenters!
0:10:21 > 0:10:23We have built our very own arch.
0:10:23 > 0:10:25So let's have a closer look at the blocks.
0:10:25 > 0:10:28What do you notice about their shape?
0:10:28 > 0:10:30They're thinner at the bottom.
0:10:30 > 0:10:34That's right, the blocks are thinner at one end and that helps them
0:10:34 > 0:10:38to fit together tightly because these blocks,
0:10:38 > 0:10:41they are not glued together, they stay in place
0:10:41 > 0:10:45because they're pushing against each other and holding themselves up.
0:10:45 > 0:10:48That's amazing, Nina!
0:10:48 > 0:10:52And another incredible thing about arches is they get even stronger
0:10:52 > 0:10:55when they have something to hold up.
0:10:55 > 0:10:56So let me show you.
0:10:56 > 0:10:59Would you like to try standing on our arch?
0:10:59 > 0:11:01- BOTH: Yeah!- Yeah? OK!
0:11:01 > 0:11:05Right, Dylan, you're first. So get onto the starting block there.
0:11:05 > 0:11:07Lovely! Whoa! Ho-ho-ho!
0:11:07 > 0:11:10Good work, excellent!
0:11:10 > 0:11:12OK, Phoebe.
0:11:13 > 0:11:18Take a nice big step up into the middle. OK, and stop there.
0:11:18 > 0:11:21Wow! That really is a strong arch.
0:11:21 > 0:11:24The hard blocks are pushing tight together.
0:11:24 > 0:11:28- Do you think the arch is holding you up?- Yeah.- It is!
0:11:28 > 0:11:30When there's a weight on top of the arch,
0:11:30 > 0:11:34it pushes all the blocks together, making it even stronger.
0:11:34 > 0:11:37# Nina and the Neurons. #
0:11:39 > 0:11:44So your question was, why do people use arches in buildings?
0:11:44 > 0:11:46And I think we've answered it.
0:11:46 > 0:11:48Arches are a really strong shape.
0:11:48 > 0:11:52They can hold up heavy things like trains.
0:11:52 > 0:11:54Whoop-whoop!
0:11:54 > 0:11:59We build buttresses on the sides of arches to help them keep their shape.
0:11:59 > 0:12:03Arches are often made of hard stone that doesn't squash easily.
0:12:03 > 0:12:06The stones in an arch are thinner at one end
0:12:06 > 0:12:10so they fit together tightly and make the arch even stronger.
0:12:10 > 0:12:12So I hope that's answered your question.
0:12:12 > 0:12:15BOTH: Thanks, Nina. Bye!
0:12:15 > 0:12:18You're welcome. Bye!
0:12:18 > 0:12:23If you want to know more about the science that's all around us,
0:12:23 > 0:12:26go to the Nina section on the CBeebies website.
0:12:26 > 0:12:27Have fun!
0:12:27 > 0:12:30# Super structures Super structures
0:12:30 > 0:12:33# Super structures Super structures
0:12:33 > 0:12:35# Super structures
0:12:35 > 0:12:38# Some of them are tall Some of them are wide
0:12:38 > 0:12:43- # They're bumpy, lumpy, wiggly too - Wiggly too
0:12:43 > 0:12:46# Some of them are strong Some of them are small
0:12:46 > 0:12:47# Like me!
0:12:47 > 0:12:49# They're windy, whirly, whooshy too
0:12:49 > 0:12:51# All around
0:12:51 > 0:12:52# Look over here
0:12:52 > 0:12:56# Build it, stack it, pile it up
0:12:56 > 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
0:13:14 > 0:13:18# Some of them are cosy warm Some of them are chilly
0:13:18 > 0:13:21# Keep us safe and hide us too
0:13:21 > 0:13:22# Hide us too
0:13:22 > 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 > 0:13:36# Build it, stack it, pile it up
0:13:36 > 0:13:39# Come on, let's get building
0:13:39 > 0:13:41# Building, building, building
0:13:41 > 0:13:44# Race it, hold it, make it stick
0:13:44 > 0:13:48# Come on, let's get building
0:13:48 > 0:13:52# Come on, let's get building! #
0:13:52 > 0:13:56And remember, there are super structures everywhere.
0:13:56 > 0:14:00Whether they're big or tall, wide or small, we can all get building.
0:14:00 > 0:14:02See you again soon. Bye!
0:14:02 > 0:14:04# Nina and the Neurons. #
0:14:04 > 0:14:06- ALL: Bye!- Get building!