Lesson video

Hello everybody and welcome to our fourth science lesson.

I am so excited to be here with you, I hope you're looking forward to our science lesson, you might be thinking, why is Miss Emms wearing such a bright jacket? The answer to that question is because this is a very reflective material.

And today we're going to be learning all about reflective materials and non-reflective materials.

So, let's go to our slide show so we can begin.

Okay, so our key question is which materials are reflective? And you are with me, Miss Emms. So, you should already have completed a start of lesson quiz, if you haven't completed the quiz, you can easily close the video now and you can go back to the previous activity where you'll find the start of lesson quiz, and that helps you see how much you remembered from our previous learning.

If you need to do that, then pause the video now and you can go and complete that.

Okay, the next thing we're going to do is we're going to have a think about reflective and non-reflective materials.

After that, you'll be answering some questions and then we're going to do an investigation.

Finally, there will be an end of lesson quiz, which will enable you to see how much of this lesson you have remembered.

Okay, you're going to need a few things in this lesson, but to start off, you'll just need an exercise book or piece of paper, a pencil and your science brain switched on and ready to go.

If you need to get any of those things, then pause the video now and go and get them please.

Okay, we are ready to start.

So, just to recap, we have learned what, we've learned about lights and we've learned about light sources.

So, we have learned that light is a type of energy that travels in a straight line from a light source, always a straight line.

And we've learnt that's a light source is an object that emits light and you've thought of lots of different light sources, perhaps a lamp, perhaps the sun, perhaps a Firefly, perhaps a torch, any objects that emit some light.

So, moving now to thinking about reflection.

So, when a light source emits light, that light travels in a straight line to the object.

When it reaches the object, it is reflected off the object, so reflects means that it bounces off the object, okay? So, reflection is when light bounces off an object.

We also learned the dark is the absence of light.

So when it stops, that means there's no light.

I've only ever been to one place where it was completely dark and that was when I went caving.

And that's mean, I went down to a cave really far underneath the grounds and because it was so far underneath the ground, no natural light could reach that area, there was no lights at all.

It didn't make a difference if I had my eyes closed or open, there was no light, it was completely dark.

Okay, let's think back to our last lesson where we learned about night and day.

Now, I'm going to ask you a question and I want me to just reply to your screens, help you recap your learning from last week.

Question number one is how many hours are there in a day? Can you tell your screen? Could you remember that it's 24 hours in a day? 24 hours that it takes for the earth to complete a full turn.

Why is it dark during the night? It's dark during the night, because you use that sentence starter to tell your screen, off you go.

well done, it's dark during the night because all parts of the earth is not facing the sun.

So the sun, the light and the heat from the sun can't reach our side of the earth.

Why is it light during the day? Tell your screen it's light during the day because.

Wonderful, well done, it's light during the day because all parts of the earth is facing the sun, it's light and heats can reach us.

And finally, the imaginary line that the earth rotates on is called it's what? Tell your screen, it's called it's? Good, it's called it's axis.

Well done if you've got the answers correct to those recap questions.

So, now we're going to move on to our star words.

If you do English with me, you might know that sometimes we stand up for our star words.

You might want to stand up with your hands by your sides.

And you're going to repeat the star words after me, before I explain what they mean, ready? Star words, star words, star words, your turn.

Okay, the first one is absorb, your turn, absorb.

If something is absorbed, I want you to think about if you spill something and if you use a cloth to wipe up that spill, the cloth absorbs the water, absorb means take in, absorb means? Absorb means? Well done to absolve means to take in.

Take in means? I hope you said absorb.

Absorb means? Great, to take in, well done.

The next one is reflect, your turn.

We already know what reflect means.

If light is reflected off an object, it means it bounces off the object, okay? Reflect, your time.

Okay and then we're just going to say these keywords, because we're going to learn about them as the lesson goes on, reflective, your turn.

I might say this jacket is a, is made of a very reflective material, okay? Non-reflective, I might say that this cardboard is a non-reflective material.

Okay, let's move on.

So, we're going to have a think about reflective and non-reflective materials and objects.

I want you to have a little think about the diagram you can see on your screen.

This diagram shows you what happens when light hits a dull or dark surface.

The light comes at the surface and lots of the light is absorbed, that means it's taken in, not very much of the light bounces back off and is reflective, that's what makes the object seem dark and dull, okay? If it's a non reflective material.

If a material is smooth and if a material is reflective, that means it appears to be smooth and shiny, because what happens is when a material is reflected, light comes to the material and it's straightened out and all of the light bounces off the material, okay? It's reflected off.

And that's what makes the object, or the materials seem smooth and shiny.

Some examples of dull and dark surfaces would be, cardboard, fabric and an example of a reflective material or object would be a mirror, a spoon or some foil.

And we're going to have to think about we are investigating these materials later on in the lesson.

So let's go over our key definitions here.

If a material is reflective, if a material is? It reflects light well, most of the light that hits the surface bounces off just like you can see here.

If the material is non-reflective, it does not reflect light well.

Some light bounces off the object, but most of the light is absorbed.

So here, some bounces off, but most is absorbed, that means taken in into the material.

Okay, we're going to pause that so that we can go back and look at some of those and think about what we've just learned.

You and your book are going to draw lines to match the descriptions to the type of surface.

So I want you to write out these four, I want you to write out reflective and non-reflective and you can draw a box around them if you'd like to.

And I want you to write down dull, dark surfaces and smooth, shiny surfaces, and you can draw boxes around those if you'd like to as well.

Can you just do that now, before you draw the lines, pause the video to do that.

Okay, well done, now I want you to have a think about which ones you're going to match to each other.

So if a material is reflective, does it appear dull and dark, or does it appear smooth and shiny? If a material is non-reflective, does it appear dull and dark, or does it appear smooth and shiny? Can you match the descriptions to the type of surface? Off you go.

Well done, so you should have had a reflective material, appears to be, makes means that the surface is smooth and shiny, so aligned between reflective and smooth and shiny.

And non-reflective means that the surface appears dull and dark, so aligned between non-reflective and dull and dark.

If you need to just fix that or tick it, then you can pause the video now.

Okay, let's move on.

So, hey, we've had, we've seen these diagrams already once in this lesson.

Hmm, which diagram shows how light is reflected on reflective materials, is it A or B? Which diagram shows how light is reflected on reflective materials, A or B? Can you write down A or B in your book based on what you think, pause the video to do that.

Okay, it was B, when light comes to a reflective material, most of that light is reflected off the material and there's not very much absorption, so it was B.

Can you pause the video and tick or fix if you need to? Well done, okay, let's move on.

Now, it's time for an investigation.

We are going to be investigating what materials can you find that are reflective and what materials or objects can you find that's are non-reflective? The first thing I want you to do if you're ready for our investigation is you are going to just draw this table in your book, okay? You can see you've got reflective materials on one side and non-reflective materials on the other side and aligned on the middle.

Can you pause the video and draw that table now? Well done, and as you go around and find materials, you're going to be able to write your answers down in that table, so keep it safe.

Now, you might not be able to find all of these objects, but you can see what you can find, okay? I'm going to demonstrate with a few of these and I'm going to show you how I would do it.

So, I have got, the one thing I couldn't find in my house, so I haven't got any foil, but I got everything else.

So, I've got a spoon, I've got a fork, I have got some paper, I have got a, it says jumper, it could be a jumper or any ultimate clothing.

I've got some cardboard, I've got some newspaper, I've got a mirror.

And look, you can see the reflection of the laptop already if I show you the mirror.

And you can see, I hope you can see the light.

Okay, I wonder why that is, that's because this material, this object is very reflective, it's so smooth and shiny.

And finally, I've got the wood, I've got my chopping board, some wood, okay? Now, we know, I'm going to stop sharing my screen with you now so you can see me full screen.

There we go.

So we know that if a material reflects light well, then it's appear smooth and shiny, okay? Almost looks metallic, it appears smooth and shiny.

And we can compare two, we can compare one very objects and one non-reflective object.

So, for example, if I think about this spoon, you can see already, you can see that it's really shiny, can you? And you can see that actually, if I hold up here, you can see the laptop there can you? And if I look into it, then you can see my face, you can see my reflection.

I can see my whole reflection in this spoon because it's such a, because it's reflecting lights so well that I can see my reflection.

The material is very smooth and it's very shiny and it's metallic and that means that it reflects light really well.

And even if I hold it up at different angles, I can see all of my reflection, just like a mirror.

Can you pause the video, go and get a spoon and see if you can do the same with your spoon, off you go.

Well done everybody.

I wonder, the fork 'cause it's a bit smaller, but I can see my face split into lots of different parts in the fork because the fork is also smooth and shiny, it reflects light really, really well.

Hmm, I wonder what happens if I look into the cardboard, I can't see my reflection in the cardboard.

I also notice that the cardboard is dull and it's dark, it's not a smooth, shiny surface.

It's not reflecting lights as well as the spoon.

What's happening to the light when it hits the cardboard, is it reflected or is most of it absorbed? Tell your screen, you're so right.

Most of the light is absorbed whereas with the spoon, most of the light is, or all of the light is reflected off the surface and that's why it's so smooth and shiny.

Okay, so if we go back to our slideshow, I would like you to go and find as many of those items as you can, don't worry if you can't find all of them, but find as many of those items as you can, pause the video now and go and do that.

Okay, fantastic, well done.

And what I'd like you to do, is I would like you to write down the materials that you think are reflective in this column and the materials that you think are non-reflective in this column.

Good luck with your investigation, off you go.

Well done everybody, you might have found some other materials around your house, so we can't correct those ones, but we can have a look at the corrections for the materials that I asked you to try and find.

So, you would have noticed that the foil, the spoon, the mirror and the fork were all reflective materials, they are, they all have smooth, shiny surfaces and some of them, you were even able to see your own reflection.

For example, in the mirror, look, you can see my reflection there, there's two of me, that's because the mirror is such a reflective surface, okay? It's smooth and it's shiny and you can see screen as well, okay? You may have noticed that the paper, the newspaper, the jumper, the cardboard and the wood were not reflective of materials.

You couldn't see your reflection in them, they weren't smooth or shiny, they are non reflective materials.

Okay, I hope that you have really enjoyed your learning so far, you have one more task that I would like you to do to conclude your investigation.

Can you write a conclusion for your experiment using the key words below, the words are dull, dark, shiny, metallic and reflective.

But you need to put them in the right places.

So I found that materials that were hmm and hmm were reflective, for example, then you need to put an example, one of the materials that you found was reflective.

I found that materials that were, hmm and hmm were not hmm, for example, and then an example of a material that was not reflective.

Can you pause the video and can you write out this conclusion with these words in the correct place, off you go.

Okay, well done everybody.

So, if we recap that, you should have, I found that materials that were shiny and metallic were reflective, for example, and then you could have had the fork, the spoon, the mirror, what have you found that was reflective? I found that materials that were dull and dark were not reflective, for example, and then maybe you had cardboard, newspaper, wood, paper, okay.

Fantastic learning everybody.

If you would like to share what you've learned, you can also parent or carer to share your work on Twitter @OakNational with #LearnWithOak and then I can see your great science learning.

Well done and good luck in your end of lesson quiz.