Intro Quiz: How can you change the size of a shadow?

Video: How can you change the size of a shadow?

﻿Hi there, everyone, and welcome to our science lesson. I hope you are feeling excited for another science lesson with me, Miss Emms. You're learning so much and I'm really, really proud of all of the hard work that you've done, since we started this unit all about light and darkness. Okay, right, let's make a start by going straight to our slideshow. So, here we go. And today our key question is how can you change the size of a shadow? How can you change the size of a shadow? Okay, so we are going to, you should have already done a start of lesson quiz, if you haven't done your start of lesson quiz, then can I ask you to exit this video, go back and complete your start of lesson quiz. Pause the video if you need to do that now. Okay, fantastic. Next, we're going to have a bit of a recap about transparent and opaque objects. Then, we will recap what we've learned about shadows. And then, the really fun part of this lesson is we are going to have a go at creating our very own shadow puppet theatres, which is going to be really exciting. And finally, you will be competing an end of lesson quiz. Okay, let's make a start. So, you're going to need a bit more than usual in this lesson but don't worry if you don't have it all. As normal, you will need an exercise book or paper, you will need a pencil and you'll need your brain, you've got that already. If you can, you should also find cardboard, glue or sticky tape and scissors. If you can, you're going to need those to create your shadow puppet theatre near the end of the lesson. I'm going to say now, that anytime that you're handling scissors, you need to ask for the help of your parents or your carer, okay? Right, let's move on. So, to recap, I'm going to ask you a couple of questions now, you can just say the answers to your screen. What are the two things that you need to be able to see? Tell your screen the two things that you need to be able to see. Amazing, you need light and your eyes, you need lights and your eyes. Number two, what happens when light hits an object? What happens when light hits an object? Hmm, tell your screen, when light hits an object. Great recapping, well done. When light hits an object, the light bounces off or is reflected off that object and goes back to your eye, remember, in a straight line. If it's a non-reflective material, as we learned about last time or in one of our previous lessons, then some of that light, most of that light, is absorbed. And three, what's the opening at the front of your eye called? It begins with a P, P. You're right! It's called your pupil. Wow! You remember a lot. Let's go on to our next recap questions because this is our last lesson about light and darkness. Okay, I would like you, on a piece of paper, to add the labels, sun, earth and moon. Is A the sun, earth or moon? Is B the sun, earth or moon? And is C the sun, earth or the moon? Pause the video and off you go on a piece of paper. Well done! Let's correct, so we know that A is the sun, B is the earth and C is the moon. And our recap questions about opaque and transparent materials. Here's the word, opaque. Here's the word, transparent. Hmm, is this showing something that's opaque or transparent? Because look, can't see through, and is this showing something that's opaque or transparent? Because look, you can see through. Might want to just point to your screen and say which one is opaque and which is transparent. Well done, everybody. Opaque, I can't see through, I can't see the letters, transparent, you can see through. And finally, for our recap questions, which diagram shows how light is reflected on reflective materials? So, which of these two diagrams shows what happens, how light is reflected if a material is reflective, A or B? Have a little look, have a think and tell your screen when you know. Great, B, on reflective materials most of the light is reflected off the object, whereas with non-reflective materials lots of the light is absorbed. Okay, so, moving on to a quick recap of opaque and transparent objects because we're going to need to know about those for our learning today. So, I'm going to read this, you may recognise this slide from one of our previous lessons. We're going to go back to the same definition of opaque and transparent. You can point as I read it, are you ready? Some objects allow light to pass through them, while others do not. Transparent objects, such as glass, let almost all of the light rays pass through them. When you look at transparent objects, they look clear and you can see straight through them. Opaque objects and materials, such as metal, do not allow any light to pass through them. You cannot see through opaque objects. So, can light pass through opaque objects? Show me this for yes, show me this for no. Can light pass through opaque objects? You're right! No. Can light pass through transparent objects? Yes or no. Yes! Well done. And finally, for our recap, we are going to read a passage about shadows. So, shadows are made when an opaque object blocks light. Light rays travel from a source in straight lines, and they're always straight. If an opaque object gets in the way, it stops light rays from travelling through it and this results in an area of darkness appearing behind the object. The dark area is called a shadow. During the day, the light from the sun can cause shadows when it reaches an opaque object. So, here you can see that this man is standing in front of a light source, we can assume the light source, either the sun or maybe 'cause he's inside, it's a light. And you can see his shadow because he's opaque, he's not letting light through, he's creating an area of darkness behind him, which is called a shadow. You can even see the shadow of the box, the cardboard, which is also opaque. And you did a great job in our lesson previously, of finding out which objects are opaque and create shadows and which aren't, and I was super impressed by all of your work in that lesson. So, moving on to shadow puppet theatre. You're going to need to get three things, you might've gotten at the beginning, if you don't have them, then you can do it without the cardboard, you can do it with just a piece of paper but it would be better, it would be even better if you had cardboard, glue or tape and scissors. And remember, when you are using scissors, you need to ask a parent or a carer to help. Pause the video if you need to go and get those three things now. Okay, remember, you must ask an adult to help you when using scissors. So, now you are going to have a look at my shadow puppet theatre. Okay, but first, so I'm going to go full screen, you can see me, and I'm going to show you how I made it and then I'm going to show you me using my shadow puppet theatre. So, now this is my shadow stage, it's not the best one that I've ever seen, but I think it's okay. What I've done is I had a big box of cardboard and the first thing I did is I cut the cardboard out in a rectangle shape, okay, I cut my cardboard up in a rectangle shape. Can you pause the video now? And you're going to need help with this, so don't worry if you don't have someone to help you for the moment, if you don't have someone to help you, then you can keep watching on the video and you can see me using my shadow stage at the end of the lesson. So, pause the video now and if you've got it, cut out a big piece of cardboard, ignore the paper, just a big piece of cardboard, without the hole, without the rectangle hole in the middle. Awesome, do that now. Okay, so you should have just had a piece of cardboard in a rectangle shape. The next job, and this is the tricky part, this is the part you might need help with, is cutting a smaller rectangle hole inside that. So, if you can imagine it without the paper, there was a rectangular hole here. I'm going to show you mine here. Can you pause the video and if someone's helping you, you can do that now, cutting a rectangular hole in the middle, pause and do that now with help. Okay, and then the third step is I then got a piece of paper and the paper has to be stuck behind, okay, so if I stick my paper behind then my paper goes over the back of the hole. So, I stuck it around, I put glue on the cardboard at the edges and I stuck my paper. Your paper needs to be big enough to go over the whole back of the rectangular hole that you made. Pause the video and do that now. Amazing, well done, you're doing such a good job. Next is when I used my pen, so I used a black pen to write shadow stage. You could call yours shadow stage, you could call yours a shadow puppet theatre, or you could even think of an imaginative name for your theatre, perhaps. And then I would like you to, if you want, you can draw some people down here and at the sides who are watching the theatre. Okay, fantastic. You should have paused to do that. And finally, I drew some curtains, it's hard for you to see, but can you see, I drew a curtain here and a curtain here to make it look even more like a theatre. Pause if you want to draw your curtains. Okay, now you need to put that to the side and it's time for you to think of what characters you're going to create, this is the fun part. So, I've made what looks a little bit like a dinosaur and a cat or a tiger. Okay, so you just need to draw the animal that you'd like to have on a piece of cardboard, draw the outline and then cut it out. So, for example, like this and like this, you don't have to use the cocktail sticks, you can just use your hands but I've used those to stick to the end of them, so that I can use them behind the shadow stage. So, pause now and create your characters, off you go. Amazing and next, you are ready to watch, to see my shadow theatre and you'll notice that the lights go down a bit because you have to do this in a dark environment because I'm using, say for example, I'm using this lamp and I'm placing it behind my shadow theatre. Okay, so I've got my lamp and that needs to go right behind the shadow theatre. Okay, right behind and then you use the characters here or this way up. Okay, so let's have a look at my shadow theatre in action. Okay, so here it is, my shadow stage. I hope you can see it from where you are, so you will be able to see, at the moment I know that you can't see my face that's because I'd like you to be able to see the shadow puppet stage, so I've called it a shadow stage, you might call yours your shadow puppet theatre or something along those lines, as your title. Now, I have explained already in the video, what you need to do to be able to make your shadow stage, just to explain, mine is just made of cardboard and then I've cut out a rectangle and stuck a piece of paper. So, the cardboard is completely opaque, the paper is normal paper, if you've got tissue paper or baking paper, that's even better because it lets more light through, okay, but this paper is letting some light through. So, what I've also done is I have made some characters, so some animals, by using cardboard and I've just stuck a cocktail stick into the end of it. You could just hold your cardboard character, if you'd like to. I've got two characters that I've made, two animals. Okay, now, I want us to have a look at what happens, so I'm going to hold, I've even drawn some little people who are sitting here, you can't see very well, but you could draw some people who are sitting in your theatre. Okay, let's start with my tiger. If I put my tiger far away from the light source, so now I'm holding it right up against the stage, as far away from the light source as possible, look, that's really clear, isn't it? And the shadow is quite small. Look, what happens if I move my tiger towards, closer to the light source, so my lamp is behind, I'm moving it closer to the lamp. The shadow is getting b-b-b, bigger, well done. So, my lamp is here behind my shadow stage, I'm going to do that again. If I put my tiger close, far away from the light source, the lamp, the shadow is small. I can change the size of the shadow by moving it closer to the light source, bigger, bigger, bigger. And now it's very close to the light source, you can barely even see it. I move it again, close, further away from the light source, closer to the stage, and it gets smaller. And look, I can make him move along. Maybe he's walking from one side, do, do, do, do, do, to the other side. Let's try it with my next character. So again, if I hold the character far away from the light source, will my character, my shadow be small or big? Tell your screen. Yeah, you're right, far away from the light source, there we go, far away from the light source, my character is small, closer to the light source, getting bigger. Smaller, further away from the light source, bigger, as we go closer to the light source. Hmm, I wonder if I can have a go at using both and maybe they can meet each other. Are you ready? I'm going to have this one first, maybe this one's there first and he's walking along. And then he meets another character, he meets the tiger. And they have a conversation, maybe this one jumps up and down and this one jumps around as well. You can have lots of fun with your shadow puppet theatre, once you have made it. The key thing for us to remember is that the closer we get to a light source, the bigger the shadow, the farther away we get from the light source, the smaller the shadow, okay. Okay, everyone, well, I hope you enjoyed watching that. I hope you've enjoyed making your own and I'm really proud of all the really hard work that you have done in this lesson. Let's go back to our slides now. You've had to go and let's just answer some final recap questions. So, question number one, how can we make a shadow smaller? Do we move it closer to the light source or farther away from the light source? Tell your screen. You're right, we move it farther away from the light source to make it smaller. How can we make your shadow larger? Tell your screen. Great, we can make a shadow larger by moving it closer to the light source, well done. Finally, I'd just like you to write a conclusion to your experiment today. So, using the words closer, further away from, smaller and larger, can you complete this conclusion? You're going to write, I found out that you can change the size of a shadow by, what can you do to change the size of a shadow? When you move an object, mm, to the light source, the shadow becomes, mm. When you move an object, mm, from the light source, the shadow becomes, mm. And that's where you'll need those four words. Here, you need to think of your own rest of your sentence. Pause and in your book or on your piece of paper, write down your conclusion, off you go. Amazing, well done. So, you should have had, I found out that you can change the size of a shadow by, something like, moving an object closer and farther away from a light source. When you move an object closer to the light source, the shadow becomes bigger. When you move an object further away from the light source, the shadow becomes smaller, or the other way round, you could have swapped it, so it was the other way around. Okay, and now it's time for you to exit the video, when it finishes and complete your end of lesson quiz. See how much you've learnt from today's lesson, I'm sure you've learnt loads and I'm really proud of you all. If you'd like to share any pictures of your shadow stage, which I would love to see, then you can ask your parent or carer, remember, you must ask somebody to do it for you, share a picture of your work on Twitter @OakNational with #LearnWithOak. Or you might want to show someone else in your household or keep it and play with it later, put on your own little show with your shadow stage. Okay, everybody, great job today. I'm really proud of all the hard work you've done and I've loved teaching this lesson. Bye, everyone.

Exit Quiz: How can you change the size of a shadow?

Completed: How can you change the size of a shadow?

In this lesson, we will be learning how you can change the size of a shadow. You'll have a go at creating your own shadow puppet theatre. You will need a pencil, a piece of paper, and if you've got them, some cardboard, a pair of scissors and a glue stick. You must ask for the help of an adult when using your scissors.

Science

How can you change the size of a shadow?

Introductory Quiz

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Final Quiz

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