MUSIC PLAYING
Hi, everyone, I'm Mwaksy. I'm Greg. Hey.Hey, Greg, so, question.You know how there are electric circuits all around us? Yeah?How is it that we don't get an electric shockwhen we touch the TV or turn on a lamp?That's a really good question.So if electricity did pass through a material then through our bodies,we would get an electric shock.But there are some materialsthat don't let electricity pass through them.The materials that do let electricity pass through themare called conductors.The ones that don't let electricity through are called insulators,and they're the ones that are really importantfor keeping us safe from electric shockswhen we use electric circuits.
OK! I think I've got it, but I'm going to need youto show me the science! All right, let's do it.I've set up a little circuit experiment here.There's a low-voltage battery,a bulb, and a gap.That bit's important.I've got two spoons. One is plastic, one is metal.I'm going to try each one in turn filling the gap,to see which one lets the electricity flow through.We'll be able to tell which one completes the circuit,cos the electricity will flow all the way roundand the bulb will light up. Yeah.
So my question to you, Mwaksy, is……which spoon is going to be the best insulatorand which spoon is going to be the best conductor?OK. Well, I believe the metal spoonwill let electricity flow through it,so I'm going to say this is going to be the best conductor.OK. Shall we give it a go? Go ahead!All right. Plastic spoon first, then. OK.Nothing. OK, all right,let's swap it for the metal spoon.Go on, go on, go on, go on.Yeah! Oh, my God, that's working! Brilliant.So I was right! Yeah. So the metal spoonallows electricity to flow through it more easilycompared to the plastic spoon. Yeah.Making it the better conductor, yeah. I am a genius!So the reason I don't get an electric shock when I touch my TVis because I'm touching plastic, which we know is a great insulator.Yeah, you've got it. Metal is one of the best conductors,which is why we use it for the wires in our circuits,for our power cables,and lots of the electronic equipment inside our TVs and phones.But on the outside of TVs, phones, and in fact most electrical cables,you'll likely find an insulator like plastic or rubberbecause it won't let any electricity through.So you're right - that is why your TV is safe to touch.I should say, though, that unfortunatelyour bodies are very good conductors,and that's why it is so important to be careful with electricity.We should never touch the conductor in a circuitwithout proper protection,and we should always be very careful around plug sockets.So to work with electricity and use it safely,we need to understand which materials are good insulatorsand conductors, right? Yeah. That bit is so important.Ooh. So do we have time for one more demo? Go on, then.
Right then, Mwaksy, you know howI love to experiment with different materials?I thought we'd try something a little bit different -we'd make a circuit using dough.Yum! So two different types of dough here -one of them is a good conductor,one of them is a good insulator.I'm not going to tell you which one's which. OK.But we're going to discover it by building a circuit. Oh, fun, OK!This sounds good. Which one should we start with? Er, this one. OK.Cool. All right, so,let's connect the low-voltage battery into it like this. Yeah.Now if you put the LED, the bulb, across the gap…Dum-de-dum…No! Nothing.OK, all right. Let's move it to the next one, then.Greg! It lit up!
That means there's something in this dough which makes it conductive.What is it? So I made this onewith salt, which helps electricity flow through it.This one, instead of the salt, it's got sugar,which doesn't help the electricity flow through it. OK!Well, now we know all about insulators and conductors,how they keep us safe and how they keep electricity flowing,so I feel like now's a good time to ask them a question.OK. Your question is this.If you were to design a new material,would it be a conductor or an insulator,and what would you make out of it? Ooh. The possibilities are endless.We'll see you soon! Bye! See you!
Video summary
In this teacher resource for primary science, Mwaksy and Greg create circuits using spoons and dough, to learn about conductors and insulators, why they’re useful, and how they keep us safe.
Having discussed what some common conductors and insulators are, Mwaksy and Greg test different materials to find out which ones are good conductors of electricity.
After finding out about some useful conductors and insulators, Mwaksy and Greg test some more with ‘squishy’ circuits made of conductive and insulating dough.
Show Me the Science is a series of short films and teacher resources for primary schools, following presenters Mwaksy Mudenda and Greg Foot as they use demonstrations, experiments and animations to learn about forces and electricity.
Teacher Notes
Before watching the film:
Prior to this lesson you may wish to introduce students to other relevant topics, for example:
During the film:
Depending on your lesson’s focus, you may wish to pause the video at certain points to check for understanding, asking questions such as:
- Can you think of any conductors you might find at home? What about insulators?
- Before Mwaksy and Greg attach the spoons, can electricity jump across the gap?
- Electricians need to be very careful when they touch broken wires, and wear gloves to keep themselves safe. Should those gloves be conductors, or insulators?
Final question:
Would your new material be a conductor or an insulator, and what would you make out of it?
Discussion points for the final question:
- What different materials do you have in the classroom or at home? What are they used to make?
- Metal is a good conductor - can you think of some of the other properties of metal?
Following on from the film:
- If you have an electrical kit in the classroom, test some different common objects to see which are conductors, and which are insulators. Try using a regular pencil, compared to one shaved down at both ends (so the electricity can flow through the graphite). You could also try making your own conductive dough in the classroom - there are many recipes online.
- Before you start testing, ask your students to make their predictions. Can they think of any surprising conductors?
- Share this Bitesize guide about how to be safe around electricity.
This short film is suitable for teaching science at KS2 in England, Wales and Northern Ireland and 2nd Level in Scotland.
What is electricity? video
Mwaksy and Greg learn about what electricity is and how we generate it using movement.
How do circuits work? video
Mwaksy and Greg learn about how circuits and switches work, and why they’re so useful.
Electricity in the world around us. video
Mwaksy and Greg explore the different reasons why electricity is useful and convert the chemical energy in a battery into different forms of energy.
