warning

Content guidance

Risk assessment required - equipment

Adult supervision required

video

Lesson video

In progress...

Loading...

Hello, my name is Mr. James, and I'm really pleased to be here with you today because we're about to do some science.

So I hope that you are feeling ready too, and that you have your curiosity fully switched on and ready to go because there's lots of thinking and exploring to do.

Today's lesson is from the unit called Simple electrical circuits.

And our outcome, our learning outcome, by the end of the session, let's hope that we can build a simple series electrical circuit.

I'm pretty confident that you can do that.

Let's get started.

So what will help us on our way with our learning today is to have a few keywords ready in our minds, and here they are, some keywords or key science vocabulary.

I'll read them.

You can repeat them if you like.

The words are circuit, components, complete, incomplete, and series.

When I click on the next slide, some definitions will pop up.

These are the meanings of each of these key words.

And what would be great is if you could have a read through, see if you can remember some of those meanings.

But don't worry, because as we go through the lesson, all of these words will come up again and again.

So here we are, have a read through.

Nearly there? Well done.

Well done for reading through them all.

Don't worry, all of those words will be cropping up again today throughout the lesson.

So what's important is that we come back to them, and we will be doing that.

So let's have a look at the way today's lesson will go.

We're going to start with understanding circuits.

And when we've understood them a bit, we'll move on to building of circuits.

Aisha's, having a think about a circuit and what it actually is.

"I want to build an electrical circuit to make a bulb light up." Do you know what an electrical circuit is? An electrical circuit is a closed loop or path that electricity can flow through to make something work.

"So," Aisha thinks, "If I build my circuit correctly, I can get the bulb to work." "I know," thinks, Aisha, "that the parts used in an electrical circuit are called components." Can you name some components in a simple circuit? Yes, you can have a cell or a battery, wires, bulb, buzzer, and motor.

All electrical circuits need an electricity source, such as a cell or a battery, wires for the electricity to flow through, and a device such as a bulb, a buzzer, or a motor that needs electricity to flow through it for it to work.

"So, to make a bulb light up," thinks Aisha, "I will need a cell or battery, wires, and a bulb." Well, as you can see, Aisha found a cell and she found some wire and she found a bulb, and she fitted them together.

But wait, something's not working.

"Why doesn't this work?" she wonders.

Luckily, Jun, her friend, has got some ideas and he says, "Remember a complete circuit is a loop where the components are connected together correctly." Well, Aisha doesn't understand why the light bulb won't light up.

"This circuit is complete because the wire connects the cell to the bulb, so it should light up." And you can see exactly how she did it, with the bulb attached to a cell by a wire.

Hmm, can you help her? Take a moment to talk with somebody next to you and see if you can decide what she should do next.

Pause the video now.

Well done.

Yes, Aisha's circuit is incomplete because it is not a complete loop.

Cells have two ends.

One is a negative end, and one is a positive end For a circuit to be complete, wires must be connected to the positive and negative of the battery in a complete loop, with no gaps.

You can see an example of that here.

To make the bulb work in Aisha's simple circuit, the electricity needs to flow through the bulb and all the way back to the cell.

It can't flow from the battery to the bulb and stop there.

So let's think for a moment, what exactly is a complete circuit? I'm going to read you three statements and I want you to give me a double thumbs up when you think I read out one that sounds correct to you.

So here we go.

A complete circuit is a group of components close together.

A complete circuit is a group of components connected together in a loop.

A complete circuit is a group of components connected together in a line.

Which one did you decide? Yes, B is the correct answer.

A group of components connected together in a loop.

That's the best definition of a complete circuit.

And now we're going to look at some wires.

These wires are connected to a cell, but which of them, A, B, or C, is connected to the cell correctly? What do you think? Yes, that's right.

B is showing the correct way to connect the wires to the cell.

Now let's take it a step further.

Which of these, A, B, or C, do you think is showing a correct complete circuit? I'll give you a moment to think.

Yes, the answer is C.

What I'd like you to do is to turn to the person next to you, turn to a partner, and just explain to them why it's C.

I'll give you a moment to do that, so pause the video now.

Right, I hope you've got that.

And I hoped having the opportunity to talk to someone about it helped you to get the understanding really fixed in your mind.

We're going to move on now and we're going to work together in a group.

We're going to work together to make a circuit, to model it.

So you need one person to be a cell and one to be a bulb, and the other people will be the wires.

Make a chain of people with a bulb and cell at opposite ends.

Would the bulb light up? And why do you think this? Right, if you get yourselves ready and you can go and do that now, so we better pause the video.

So I wonder whether you've decided that your circuit will work or whether it won't work.

Will the bulb light up? So you had a chain of people with the bulb and the cell at opposite ends.

Well, did it work? Let's try another way.

Now I'd like you to turn your circuit into a loop.

All stand in a circle and hold hands to make a complete circuit.

Would the bulb light up now? And why do you think this is? You can have a chat once you've got your circuit set up.

So we need to pause the video.

Ready? Good job.

When we modelled all the components in a line, the bulb would not have lit up because the circuit needs to be a loop with no gaps for the electricity to flow through the bulb.

So let's turn our circuit into a loop.

All stand in a circle and hold hands to make a complete circuit.

I will give you a moment to do that.

Ready? Well done.

So now we're all standing in a circle, holding hands, and we are making a complete circuit.

When we modelled all the components in a loop, the bulb would have lit up because the circuit was complete.

The components were joined together correctly and there were no gaps in the circuit.

The electricity could flow from the cell, through the bulb and back to the cell.

Now we'll turn our minds to building circuits.

Aisha and Jun understand more about building circuits.

They're sounding confident.

"Electricity," Aisha says, "only flows around a circuit if it is complete." "This means," says Jun, "that all the components must be joined together so that the electricity flows through them and all the way back to the cell." "And," adds Aisha, "the electricity needs to flow from one end of the cell back to the opposite end." They're ready to build a simple circuit.

When the components they need are in a complete loop like this, the circuit is called a series circuit.

It can be a bit tricky to connect wires to a bulb, so they'll put the bulb in a bulb holder to keep it in place.

You might have some just like this in your classroom.

Jun wants to make an exciting series circuit with a cell, buzzer, light bulb, and a motor.

He plans to make a complete loop with all the components joined by wires.

Do you think this is a good way to start making circuits? Why? Take a moment to talk to a partner and tell them what you think.

Pause the video now.

Jun has certainly got some great ideas, but is he going about achieving them in the best way? He should really start with a simple series circuit with just one device.

Here in the diagram you can see he's just testing a bulb.

Or perhaps next, a buzzer.

And here, a motor.

This way, Jun can try one device at a time to make sure he understands each stage of his circuit building.

And then he can solve any problems that come up along the way.

This is how scientists work.

What is a series circuit? I'm going to read you some statements and you can decide which one describes a series circuit the best.

I'm going to ask you to wave your arms in the air like this if we come to a statement that you think is the correct one.

Ready? Let's go.

So a series circuit is.

Is it A, a set of activities you do in a loop for fitness training? Is it B, a set of TV programmes which follow one story? Is it C, a circuit where all components are in the same loop? Or is it D, a circuit where all components are in the same line? I wonder what you thought.

Well, the correct answer is.

When we're talking about circuits, the correct answer is C, a circuit where all components are in the same loop.

Well done if you've got that right.

And let's have a think about how scientists solve problems. I'm going to read you three statements, and again, I'd like you to give me a wave when you hear me read the one you think is the correct one.

So, ways that scientists try to solve problems. They try lots of different ideas at the same time to save time.

That's A.

B, they try one idea then pass the problem on to someone else.

C, they try different ideas one after the other to help them understand.

I wonder which answer you came up with.

Well, I can tell you that the correct answer is C.

They try different ideas one after the other to help them understand.

Time for you to develop your skills as an electrical engineer by building some simple series circuits.

Here are three that I'd like you to try and build.

A, circuit to light up a bulb.

B, a circuit to make a buzzer buzz.

And C, a circuit to make a motor spin.

So it's going to be a good idea to pause the video now so you can get on and make your simple series circuits.

Incredible.

Well done.

So I would now like you to note down two to three new things that you discovered when building your circuits, and you can talk about what you found out with a partner.

So again, please pause the video.

It's always good to compare notes with somebody else to hear what they found out and to tell them what you found out too.

Well done.

So you've been developing your skills as an electrical engineer by building simple circuits.

So you might record something like this.

We managed to make all the simple circuits work with the bulb, then the buzzer, and then the motor.

And you can see that here we have recorded how we did it each time.

You might like to do the same.

I suggest you take a minute to do that now, so let's pause the video.

Here are the two or three things that Jun and Aisha discovered when they were building circuits.

We found the buzzer didn't always work, the bulb wasn't very bright, the motor didn't always turn the same way.

How does that compare to what you discovered? Did you discover similar things or did you discover different things? So let's end today by reviewing all the learning that we've been doing building simple circuits.

We've learned that a complete electrical circuit is made when all components are connected together correctly.

Wires must be connected to the positive and negative end of the battery in a complete loop.

A series circuit is when all the components are in the same loop.

We've also learned today about scientists and how they work.

They try out different ideas in order to solve problems. Well done for your work as a scientist today building electrical circuits.

Great job.