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 > 0:00:17# 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 > 0:00:23- # Eyes.- Eyes! - Ears.- Ears!- Nose.- Nose!
0:00:23 > 0:00:26# Nina and the Neurons find out what you need to know
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 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 > 0:00:48- # Eyes.- Eyes! - Ears.- Ears!- Nose.- Nose!
0:00:48 > 0:00:50# Nina and the Neurons find out what you need to know
0:00:50 > 0:00:53# Nina and the Neurons find out what you need to know
0:00:53 > 0:00:54# Oh, yeah! #
0:00:56 > 0:00:57Whoop! Whoop!
0:00:57 > 0:00:59SHE LAUGHS
0:00:59 > 0:01:00One more.
0:01:00 > 0:01:05Yay! Oh, hello. I've just made my very own plastic-beaker tower.
0:01:05 > 0:01:06Oh!
0:01:06 > 0:01:10I'd better be careful. I don't want to knock them over.
0:01:10 > 0:01:11BEEPING
0:01:11 > 0:01:15I hear a beep, I see a flash, I wonder what they're going to ask.
0:01:19 > 0:01:21- ALL: Hi, Nina.- Hi, guys.
0:01:21 > 0:01:24We've got a question for you.
0:01:24 > 0:01:26Why don't tall buildings fall over?
0:01:26 > 0:01:30Great question. Why don't tall buildings fall over?
0:01:30 > 0:01:33We see lots of really tall buildings all around us
0:01:33 > 0:01:37but how do they stay up? Come to my workshop and we'll investigate.
0:01:37 > 0:01:40ALL: See you soon, Nina! Bye.
0:01:40 > 0:01:41Bye.
0:01:41 > 0:01:44I'm going to need some help to answer this one,
0:01:44 > 0:01:46and I know just who to ask.
0:01:46 > 0:01:49OK, Neurons, time to get to work.
0:02:04 > 0:02:07ALL: Neurons at the ready, Nina.
0:02:07 > 0:02:09OK. Today's question is,
0:02:09 > 0:02:11Why don't tall buildings fall over?
0:02:11 > 0:02:15Which neuron will be most useful to help find the answer?
0:02:15 > 0:02:18ALL: Me! Me! Me! Oh, me!
0:02:18 > 0:02:21Will it be fabulous Felix?
0:02:21 > 0:02:25I can help so very much if you need the sense of touch.
0:02:25 > 0:02:26Will it be beautiful Belle?
0:02:26 > 0:02:31I send messages to brain from ear. If there's a sound, I'll help you hear.
0:02:31 > 0:02:33Will it be lovely Luke?
0:02:33 > 0:02:35For looking and seeing, day or night,
0:02:35 > 0:02:38I'll help you with your sense of sight.
0:02:38 > 0:02:40Will it be awesome Ollie?
0:02:40 > 0:02:43If it's pongy or whiffy but you can't tell,
0:02:43 > 0:02:47- my messages help your sense of smell. - Or will it be baby Bud?
0:02:47 > 0:02:51Sour, salty, bitter or sweet, I'm your taste buddy whenever you eat!
0:02:55 > 0:02:56It's Luke!
0:02:56 > 0:02:58CHEERING
0:02:58 > 0:03:03Go, Luke! Go, Luke! Go, Luke! Go, Luke! Go, Luke!
0:03:03 > 0:03:06Go, Luke! Go, Luke!
0:03:06 > 0:03:09Cool, Nina. I'll be looking out to help you.
0:03:09 > 0:03:13Today's question is, why don't tall buildings fall over?
0:03:13 > 0:03:16Because tall buildings are something we can see,
0:03:16 > 0:03:19Luke, our sight neuron, will be helping us.
0:03:19 > 0:03:22But stand by, Neurons, I may need help from all of you.
0:03:22 > 0:03:26I need to get the workshop ready before the Engineers arrive.
0:03:28 > 0:03:30James loves roasting marshmallows.
0:03:30 > 0:03:33Joshua loves karate. Archie loves porridge.
0:03:33 > 0:03:36A lot of cities have really tall buildings.
0:03:36 > 0:03:38I've seen really tall buildings.
0:03:38 > 0:03:41When I build a tall tower with blocks, it falls over.
0:03:41 > 0:03:43So, today, for one day only,
0:03:43 > 0:03:47James, Joshua and Archie become the Engineers!
0:03:50 > 0:03:53- Hi, guys.- ALL: Hi, Nina.
0:03:53 > 0:03:56Welcome to my workshop. Thanks for your question -
0:03:56 > 0:03:58why don't tall buildings fall over?
0:03:58 > 0:04:01To find out, let's start by using our senses.
0:04:01 > 0:04:06Whoo-whoo! A senses experiment! We're ready, Nina!
0:04:06 > 0:04:09Making tall buildings can be very tricky.
0:04:09 > 0:04:11Why do engineers build them?
0:04:11 > 0:04:12Let's find out.
0:04:12 > 0:04:15Now, this is a long, flat building.
0:04:15 > 0:04:18James, I'd like you to look at it
0:04:18 > 0:04:23and copy the shape of it with your body on this piece of paper.
0:04:23 > 0:04:25Oh!
0:04:28 > 0:04:31Well, that's a good way to make a long, flat shape.
0:04:31 > 0:04:34Just lie down and relax.
0:04:34 > 0:04:37Now, I'd like you to draw round him using these crayons.
0:04:37 > 0:04:39Go for it.
0:04:46 > 0:04:49Excellent work. Up you get, everyone.
0:04:49 > 0:04:50Well done.
0:04:50 > 0:04:52NINA LAUGHS
0:04:52 > 0:04:55Now I'd like you to pretend to be another shape of building,
0:04:55 > 0:04:58but this time a tall, thin building.
0:04:58 > 0:05:02So, James, can you make that shape for me?
0:05:02 > 0:05:05Very good. And can you guys draw around his feet?
0:05:10 > 0:05:13Excellent! Let's look at your drawings.
0:05:13 > 0:05:15Do you see the difference?
0:05:15 > 0:05:18Lying down, James took up a lot more space
0:05:18 > 0:05:20than when he was standing up.
0:05:20 > 0:05:24He hasn't changed size, he's just changed position.
0:05:24 > 0:05:26And it's the same with buildings.
0:05:26 > 0:05:31Long, flat buildings take up a lot of space on the ground,
0:05:31 > 0:05:35whereas tall buildings stand upright and take up far less.
0:05:35 > 0:05:38This is useful in cities where it's very busy
0:05:38 > 0:05:42and there's lots of buildings squeezed into a small space.
0:05:42 > 0:05:45So let's make our own tall buildings. Follow me!
0:05:45 > 0:05:49Let's see how high we can make our building.
0:05:55 > 0:05:57NINA LAUGHS
0:05:59 > 0:06:00Oh! Oh, no!
0:06:01 > 0:06:03NINA LAUGHS
0:06:03 > 0:06:05Joshua...
0:06:06 > 0:06:08CHEERING
0:06:10 > 0:06:12Going, going...
0:06:12 > 0:06:13Oh!
0:06:13 > 0:06:16Our tall buildings have fallen over.
0:06:16 > 0:06:20And if something falls over, it means it isn't balanced.
0:06:20 > 0:06:23So, as our buildings got taller, they were harder to balance.
0:06:23 > 0:06:26And that's the same as real tall buildings.
0:06:26 > 0:06:28They're hard to balance, too.
0:06:28 > 0:06:33- The higher they get, the wobblier they can become.- Like wobbly jelly!
0:06:33 > 0:06:36Wibble-wobble! Wibble-wobble!
0:06:36 > 0:06:40But we have lots of tall buildings that don't fall down.
0:06:40 > 0:06:43How did engineers work out how to make them balance?
0:06:43 > 0:06:46Let's go and look up at something to find out.
0:06:50 > 0:06:53BELLE: Where do you think we're going today?
0:06:53 > 0:06:56- OLLIE:- Where can you look up something?
0:06:56 > 0:06:59- FELIX:- Well, that's easy. We must be going to the library
0:06:59 > 0:07:01to look up something in a book.
0:07:01 > 0:07:05LUKE: We're about to find out. Looks like we're here, everyone!
0:07:07 > 0:07:09This is where we've come to look up!
0:07:09 > 0:07:14LUKE: Whoa! That is a very, very tall building.
0:07:14 > 0:07:17- It's very tall, isn't it?- ALL: Yes.
0:07:17 > 0:07:19This is Canary Wharf.
0:07:19 > 0:07:22It's one of the tallest buildings in the country.
0:07:22 > 0:07:24ALL: Wow!
0:07:24 > 0:07:29It's the height of 55 double-decker buses all on top of each other.
0:07:29 > 0:07:31ALL: Wow!
0:07:31 > 0:07:33That's right.
0:07:33 > 0:07:35If this building was lying down,
0:07:35 > 0:07:38it would take up lots and lots of space on the ground
0:07:38 > 0:07:41and there wouldn't be room for the other buildings.
0:07:41 > 0:07:45But because it's standing up, it takes up less space on the ground
0:07:45 > 0:07:49and we can still fit lots of offices and homes inside.
0:07:49 > 0:07:52Does it look wobbly, like our buildings?
0:07:52 > 0:07:53ALL: No!
0:07:53 > 0:07:55Well, let's give it a push.
0:07:55 > 0:07:56Everyone, let's push.
0:07:56 > 0:07:58SHE GRUNTS
0:07:58 > 0:08:01ALL GRUNT
0:08:03 > 0:08:05NINA LAUGHS
0:08:05 > 0:08:09No, no wobbles there. So, how do they make buildings less wobbly?
0:08:09 > 0:08:13Let's do a little experiment to find out. Come with me.
0:08:15 > 0:08:19Now, here we have three different-sized rectangular boxes.
0:08:19 > 0:08:22We know from our building-blocks experiment
0:08:22 > 0:08:25the taller the building, the harder it is to keep balanced.
0:08:25 > 0:08:27Which one do you think is
0:08:27 > 0:08:29most likely to fall over?
0:08:29 > 0:08:31The tall blue one.
0:08:31 > 0:08:32Well, let's see.
0:08:32 > 0:08:34Let's pretend to be the wind
0:08:34 > 0:08:36and we'll try and blow them over.
0:08:36 > 0:08:40ALL BLOW
0:08:40 > 0:08:41NINA LAUGHS
0:08:41 > 0:08:42Oh!
0:08:42 > 0:08:43Oh, well done.
0:08:43 > 0:08:47And you were right - this building was much easier to blow over
0:08:47 > 0:08:51because it's tall and thin and more difficult to balance -
0:08:51 > 0:08:53because of something called balance points.
0:08:53 > 0:08:57Balance points? What are balance points, Nina?
0:08:57 > 0:09:00Well, Ollie, I have the perfect way to show you.
0:09:00 > 0:09:03If you guys can take a box each...
0:09:03 > 0:09:06I'd like you to draw a line
0:09:06 > 0:09:09from one corner at the top
0:09:09 > 0:09:12to the opposite corner at the bottom.
0:09:18 > 0:09:22Excellent. Now draw another line between the other corners.
0:09:31 > 0:09:33Well done, guys. They look fantastic.
0:09:33 > 0:09:36Now, have a look over here because...
0:09:36 > 0:09:40these are the balance points.
0:09:40 > 0:09:43They're in the centre of the box, where the lines meet.
0:09:43 > 0:09:46Looking a the lines on these boxes,
0:09:46 > 0:09:49which one has the highest balance point?
0:09:49 > 0:09:50The tall building.
0:09:50 > 0:09:54Yes. Tall buildings have a high balance point
0:09:54 > 0:09:57and short, flat buildings have a low balance point.
0:09:57 > 0:10:00Because our tall building has a higher balance point,
0:10:00 > 0:10:03it's easier to blow over.
0:10:03 > 0:10:07To make a tall building less wobbly, engineers lower the balance point.
0:10:07 > 0:10:09Look at this picture of Canary Wharf.
0:10:09 > 0:10:12Some of the building is below ground,
0:10:12 > 0:10:14so the balance point is lower, too.
0:10:14 > 0:10:17The part of the building below the ground
0:10:17 > 0:10:19is called the foundations.
0:10:19 > 0:10:22Foundations help make a building less wobbly.
0:10:22 > 0:10:25Let's go back to the workshop to find out how.
0:10:26 > 0:10:28Have a look over here, boys.
0:10:28 > 0:10:33Now, the grey bit on this building here will be our foundations.
0:10:33 > 0:10:37The foundations are the bits of a building that go under the ground.
0:10:37 > 0:10:40Let's put this building with the foundations
0:10:40 > 0:10:42into this nice piece of grass here.
0:10:42 > 0:10:46And the foundations fit underneath.
0:10:46 > 0:10:47Oh.
0:10:47 > 0:10:51And let's sit the building without foundations
0:10:51 > 0:10:53just beside it here.
0:10:53 > 0:10:57So they are the same height. The only difference is,
0:10:57 > 0:10:59this one is pushed into the ground.
0:10:59 > 0:11:01So let's see how wobbly they are.
0:11:01 > 0:11:04- Joshua, take a big, deep breath... - SHE BREATHES IN
0:11:04 > 0:11:08..and after three - one, two, three, blow!
0:11:08 > 0:11:10HE BLOWS NINA LAUGHS
0:11:10 > 0:11:12And the red one.
0:11:12 > 0:11:13HE BLOWS
0:11:13 > 0:11:14Oh!
0:11:14 > 0:11:16NINA LAUGHS
0:11:16 > 0:11:20Oh, we easily knocked over the building without foundations.
0:11:20 > 0:11:22But this one didn't move.
0:11:22 > 0:11:24Not even if I give it a push.
0:11:24 > 0:11:29Foundations also let the ground grip onto the bottom of the building.
0:11:29 > 0:11:33Just like when we grip something...
0:11:33 > 0:11:35we can hold it still. You try.
0:11:38 > 0:11:40And give it a push. That's it.
0:11:40 > 0:11:42How does it feel?
0:11:42 > 0:11:43Hard to move.
0:11:43 > 0:11:47It is, isn't it? The ground grips the bottom of the building
0:11:47 > 0:11:49like our hands are doing to the rulers.
0:11:49 > 0:11:51Foundations are engineers' way
0:11:51 > 0:11:54of making sure that tall buildings don't fall over.
0:11:54 > 0:11:57# Nina and the Neurons! #
0:12:00 > 0:12:03So, your question was, why don't tall buildings fall over?
0:12:03 > 0:12:05I think we've answered it.
0:12:05 > 0:12:09We discovered that engineers added foundations to a building,
0:12:09 > 0:12:12an extra part of a building that goes under the ground.
0:12:12 > 0:12:15Foundations make a building less wobbly
0:12:15 > 0:12:18by letting the ground grip onto the building
0:12:18 > 0:12:19and help keep it up.
0:12:19 > 0:12:24- So I hope that's answered your question.- ALL: Thanks, Nina. Bye!
0:12:24 > 0:12:26You're welcome. Bye!
0:12:29 > 0:12:33To know more about the science and engineering all around us,
0:12:33 > 0:12:37go to the Nina section on the CBeebies website. Have fun.
0:12:37 > 0:12:39- # Pulling.- Pushing. - Twisting.- Mixing.
0:12:39 > 0:12:43- # Drilling.- Squeezing.- Floating. - Go engineering
0:12:43 > 0:12:45# Go engineering!
0:12:45 > 0:12:50# When you need to fly it, make it, shape it
0:12:50 > 0:12:55- # Go engineering - Go engineering!
0:12:55 > 0:12:58# When you want to build, go engineering
0:12:58 > 0:12:59# Engineering!
0:12:59 > 0:13:04# When you've got to solve a problem but you don't know how to do it
0:13:04 > 0:13:07# It's time to go engineering
0:13:07 > 0:13:08# Engineering!
0:13:08 > 0:13:13# When you want to lift it, stick it, pop it, bend it
0:13:13 > 0:13:16# It's time to go engineering
0:13:16 > 0:13:18# Engineering!
0:13:18 > 0:13:22- # Go engineering - Go engineering!
0:13:22 > 0:13:25# When you need to fly it, make it, shape it
0:13:25 > 0:13:27# Engineering!
0:13:27 > 0:13:31- # Go engineering - Go engineering!
0:13:31 > 0:13:36# When you want to build, go engineering
0:13:36 > 0:13:38# Go engineering! #
0:13:38 > 0:13:40I've had a brilliant day.
0:13:40 > 0:13:45I liked it when everyone's building blocks came tumbling down.
0:13:45 > 0:13:49It's been such a great day, man.
0:13:49 > 0:13:53I could hardly see the top of the building, it was so tall!
0:13:53 > 0:13:55It's been a marvellous day.
0:13:55 > 0:13:59The building with foundations was no pushover!
0:13:59 > 0:14:02Engineers help to build the world around us.
0:14:02 > 0:14:06They make things work and use science to solve problems.
0:14:06 > 0:14:07See you again soon. Bye.
0:14:07 > 0:14:09Bye, Nina!
0:14:09 > 0:14:12Subtitles by Red Bee Media Ltd