Key Stage 2

Light

Tom Robson – Supporting Primary ScienceSeptember 2012 (2nd revision DRAFT)

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Year 4 Light Notes and GuidancePupils should be taught to:

explain how shadows are made when a light source is blocked by something that is not transparent [168]

investigate the size of shadows. [169]

Ensure pupils continue to practise discussing how light travels from a light source into our eyes. In Key Stage 1, pupils were taught about light sources, including the Sun, and that we use our eyes to see objects. [170]

Pupils can apply their knowledge and skills by:

exploring and discussing shadows and how they are made (on a wall, the playground, in stories) when the light source (a torch, lamp, the Sun) is blocked by something that is not transparent.

making shadow puppets and projecting them onto a screen, exploring how to make the shadows bigger and smaller, and looking for patterns in shadow size. Pupils can set up and perform comparative tests on shadow formation, record their findings (taking accurate measurements and using simple scientific language, drawings, labelled diagrams, bar charts or tables), report on their findings including presenting written explanation, and use their results to suggest improvements and predictions for setting up further tests.

showing that we see things because light reflected from them enters the eye – pupils can build a ‘set’ inside a box with a peep hole and a hatch that can be opened to let in light, demonstrating that the set is only visible through the peep hole when the hatch is open. [171]

Pupils should not be formally introduced to the idea of rays of light at this

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Year 6 Light Notes and GuidancePupils should be taught to:

explain that objects are seen because they give out or reflect light into the eye, using results of any comparative tests. Explain the scientific idea that light travels in straight lines from a light source or is reflected from a surface into the eye [259]

explain that light can be broken into colours and that different colours of light can be combined to appear as a new colour [260]

explain how the ray model of light explains the size of shadows [261]

use simple optical instruments. [262

Ensure pupils are introduced to the idea of a predictive model through light – that light travels in straight lines, so we can think of it as a ray. Using this model, we can explain and predict the size of shadows and pools of light.[263]

Pupils can apply their knowledge and skills by: being introduced to the idea that we see things because light enters the eye. studying the story of Isaac Newton (built the first reflecting telescope). investigating how to change the size of a pool of light and the size of shadows, using the ray model to

explain their findings. making a periscope and examining how it works by reflecting light between mirrors. using a ray box or shining a torch through a slit in cardboard to make rays. demonstrating how light splits into different colours when it passes through a prism, and relating this

to how a rainbow is formed. colouring sections of a card circle in red, blue and green and demonstrating how spinning the disc

results in the card appearing white. using some simple optical instruments, for example a mirror, magnifying glass, binoculars, telescope

and microscope. [264] Teachers should be aware that the effects of mixing different colours of light are not similar to the

effects of mixing different colours of pigment, but do not need to explain the difference to pupils. [265]

In Year 6, ensure pupils are planning investigations,

including recognising and controlling variables where appropriate. they should be taking measurements using a range of scientific equipment, with accuracy and precision, using

stopwatches, seconds (s) and minutes (min), temperature in degrees Celsius (°C) using a thermometer, mass in grams (g) and volume in millilitres (ml).

they should record their data using scientific diagrams and labels, tables, bar and pie charts, line graphs or models, and report their findings, including written explanation of results, causal explanation and conclusions.

they should be presenting their reports in written form, or as displays or presentations, and using their results to make predictions for further tests. [266]

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Bright/brighterCandleColourDark/darkerDim/dimmerEmitsLight beamLight rayLight sourceLight/lighterMirrorOpaquePrismReflect/reflectionShadowTorchTranslucentTransportTravel

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Medium Term Planning page Year 3 & 4 Topic (3/4 weeks) Highlight the skill area you need to improve over this next topic

Planning investigations Selecting equipment (5)

Collect data: What are we measuring or observing? (5) Collect data : What might affect what

we are observing or measuring? (5) Ask planning questions (5)

Predict what might happen (5)

Gather evidence (5) Identify risk (5)

Working with evidence: Using evidence to explain (2) Describe what has been found out with reasons (3) Think about spooky results (errors and anomalies) (1) Suggest improvements (1)

Thinking scientifically: Use models to help us explain things Generate ideas (1) New evidence can change our ideas

How we use evidence (1)

Communicating and collaborating

Communicating scientific ideas Use scientific words and symbols appropriately Working together (1)

B. Investigating shiny materials and reflection – how do you think light gets to our eyes?

C> Exploring what makes a shadow. What do you think might happen to the (darkness) shadow if we change the …?

A. Exploring light sources and reflection – what do you think happens to the light if we shine it on different

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Medium Term Planning page Year 5 & 6 (3/4 weeks)Topic Title Highlight the skill area you need to improve over this next topic

Planning investigations Selecting equipment (6)

Collect data : What are we measuring or observing?(6) Collect data : What might affect what we are observing or measuring? (6) Ask planning questions (6)

Predict what might happen (6)

Gather evidence (6) Identify risk (6)

Working with evidence: Using evidence to explain Describe what has been found out with reasons Think about spooky results (errors and anomalies) Suggest improvements

Thinking scientifically: Use models to help us explain things (2) Generate ideas (3) New evidence can change our ideas How we use evidence

Communicating and collaborating

Communicating scientific ideas (3) Use scientific words and symbols appropriately Working together

A-Exploring light sources and

reflection – what do you think happens to the light if we

shine it on different surfaces? Exploring

colour

B- Investigating shiny materials and reflection –

how do you think light gets

to our eyes? Exploring

bending light

C-Exploring what makes a shadow. What do you think might happen to the (darkness) shadow if we

change the …and keep the same x,

y and z?

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Colour coding refers to the activities that follow in the rest of the document.Year 3 and 4

Knowledge and Understanding

Skeleton of topic(Light)

Year 5 and 6Knowledge and Understanding

Objects look dark when there is no light falling on them. You can use a mirror or any shiny surface to reflect light.

Light source:Materials that reflect light. What is colour?

Light travels in straight lines unless it hits an object (like a mirror), or passes onto a new material (like a lens). All surfaces reflect light but some do it better than others. The smoother the surface the better it is at reflecting. White light is made up of 7 different colours

The shinier the material the better it reflects. How light gets into the eye

Light source:How we see light

We see lightning before hearing the thunder because sound travels much more slowly than light.Can draw a diagram to show how light comes from a source, hits something and is reflected from it to the eye.

That some materials let light through them; while others let a little through and some let none through. Can link the formation of a shadow with light not getting through the material. Objects look dark when there is no light falling on them. Can predict which materials will make good shadows.

shadows (ray model of light)

Language – transparent, translucent and opaque – match to material, shadow and light transmission through the material. Opaque materials absorb light – it cannot pass through them. Can explain shadows as an area of less light due to a material preventing light from getting through.

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LOWER A Exploring reflections.

How do we see light? Generate ideas Ask children to think of as many things as possible which give us light. In groups, can they draw a picture or make a poster of light sources? Display and discuss these. Ask children to choose one of the light sources they have drawn and to draw or write down their ideas about how they see the light

How do we see light? Describe what has been found out with reasons Can children explain why they cannot see in the dark?Ask them to write or draw a simple explanation before discussing their ideas as a class. (It is important to check they understand that they cannot see in the dark because of absence of light.) Children could use a dark box to reinforce this idea. Use a show box lined with dark paper with a small hole at one end to look through. Place an object in the box and let children look through with lid on and with the lid off. What do they notice? Can they explain their observation?

What do you think happens to the light if we shine it on different

surfaces?

Investigate: Where have you seen your reflection? Can the children suggest anything in which they can see their reflection at school or in the playground? Go on a reflection hunt around the school and the playground and find things they can find their reflection in. Make a list of all the places. Where can they see their reflection best?What makes a difference to how well a surface or object reflects an image? Possible ideas might be: shininess of material, surface of object, curved or flat surface, colour of object, distance of mirror from object, size of object, etc.

Into complete ones using a mirror. Which upper case letters of the alphabet look the same in a mirror? Set the children the task of finding different things without moving. Get a child to sit on a red cross (no moving!) and ask him or her to find different places or objects around the room using a mirror.

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DRAFTUPPER – A Exploring reflections.

Exploring reflection Generating ideas: Using a collection of objects with shiny and dull surfaces, let the children shine a torch on them and ask them to observe what happens with each object. Encourage them to discuss and record their observations.What do they notice about the light reflecting on shiny surfaces? Do they notice a difference with the dull surfaces? What conclusions can they make? Why do some surfaces reflect light better than others? Get the children to look at the surface of a shiny and dull object through a hand lens or a microscope. Do they notice a difference?Make a collection of materials and objects that are reflective. Make a collection of reflectors used in everyday life, e.g. cats eyes, bicycle lights, reflective clothing. Let the children shine a torch at them. What do they notice? Can they add to the collection? e.g. armbands, road signs. Link with road safety, e.g. having lights on bikes, wearing reflective bands when dark, etcAsk children to explain how they see the light from the torchStick small coloured paper circles onto a card (use about ten colours) and place them on the inside at the end of a show box. Make five or six holes in the side and cover them with masking tape. Children can then look through a spy hole made to one end of the box. They should not be able to see anything. By removing the tape from one hole at the time, they should see the colours appear. Ask them to list the colours in the order they appear. Which colours would they wear if they wanted to be seen in the dark and gloom

What do you think happens to the light if we shine it on different surfaces?

Children could investigate shining a light source on different surfaces (card, fabric, paper) that vary in thickness, colour, size, texture, etc. Which surface shows the light best of all?Investigation – What makes a difference to how easily you can be seen in the dark? Possible ideas might be: colour of clothing, use of reflective materials, distance etc

Ask children to make a poster called ‘How to be seen in the dark’ to display in school. Can the children make a poster showing how mirrors are used in everyday life, e.g. on cars, in shops, at the dentist? Encourage them to find out information on mirrors from books.

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Light Sources: Exploring reflections.A

Level 1Knows that light comes from the Sun, light bulbs, candles. Language: Sun, light, dark, bright, dim, morning, night, day, candle, torch, shadow. I can see myself in a mirror.

Identify the objects, (eg sun, moon, torch, luminous jacket, candle, cats’ eyes) that give out light. From the selection match the words (from the list above) to different pictures.What can you see yourself in?

Level 2I can see in the light but not in the dark. Some light must be there to see. The brighter the Sun the more light there is. Some things give out more light than others. Language: shiny, dull, reflect. Can sort things into groups depending upon how reflective they are. Can sort things into groups depending upon how bright they are.

Describe a time when you couldn’t see very well, eg fireworks night, trick or treating

When can you not see?On which of these days will it be brighter: cloudy, rainy, sunny?Put these materials into groups based on how shiny they are: glass mirror, plastic sheets, felt, card, paper, metal strips etcPick random objects out from a bag/box. Pupils must describe as either shiny or dullShow me what shiny/dull is like – act it out with a friend

Level 3Objects look dark then there is no light falling on them. You can use a mirror or any shiny surface to reflect light. The shinier it is the better it reflects.

Tell me what objects look like in the dark.What can you use to reflect light?(in a light room) Name things you can see clearly(in a darkened room). Now tell me what’s happened to those itemsUse the torch and change the different materials (tin, foil, mirror, cardboard) to make the light bounce (“reflect”) somewhere else in the roomWhich materials made the light reflect best? Describe what these materials are like (ie shiny not dull)

Level 4 Record (draw/write) how light travels from the source to the eye Link smoothness of a surface with how well it reflects

Light travels in straight lines unless it hits an object (like a mirror), or passes onto a new material (like a lens).All surfaces reflect light but some do it better than others. The smoother the surface the better it is at reflecting. We see lightning before hearing the thunder because sound travels much more slowly than light.

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Why do you think we cannot see around corners? What do you think we can use to see around corners?What surfaces do you think make the best reflectors? Why do you think we can see lightning before you hear the thunder?How do you think light travels to our eyes from the thing we are seeing?Level 5

Explain how we can see Record (draw/diagram) an explanation of how we see colour Link what you know about reflection and how we see colour Model how a smooth surface reflects light and how a rough surface reflects lightLight is reflected off all surfaces and if it then passes into my eye I will see the object’s surface; some objects reflect only certain colours and so they appear coloured. The actual colour they appear depends on the light colours of red, green & blue that is being reflected. Blue objects reflect only the blue light. Why do you think some things appear red and others blue?

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Lower – B Light travelling to the eyeDescribe what has been found out with reasons Let children shine a torch in a dark place onto a piece of card stuck on a wall. To show that light exists between the torch and the wall (although it may appear invisible), children can see the light is travelling by blocking the light halfway between the torch and the wall with another piece of card.

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DRAFTUsing evidence to explainLight a night-light and stand it in a metal tray containing sand. Can the children explain how they see the candle flame? Ask them to draw a picture to illustrate their explanations. Discuss the drawings as a group or class. Talk about light travelling from a source in simple terms, i.e. the light from the candle travels to our eyes

Working togetherLet the children explore what they can see with one mirror and what they see behind them?Can they see to one side?Can they catch a spot of light and move it round the classroom?Can they count their teeth with their tongue and use a mirror to check?Can the children use a mirror or mirrors to see round a corner?

Working in groups, can the children think of a way to send a ‘light’ message round a corner from one child to another? The children could draw a picture to explain how their ideas work. Give the children some half shapes and half pictures and let them make them

Upper – B Light travelling to the eye.

Investigation – what makes a difference on how well you can see round a corner using a mirror? Possible ideas might be: mirror size, mirror angle, distance of mirror from corner, shape of mirror

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DRAFTInvestigation: Let children experiment using two mirrors and a small object, e.g. toy animal. How many animals can they see? What happens if they use two, three or more toy animals? What happens if they change the angle of the mirrors? Can they explain why they can see several images or draw a diagram to show what is happening

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Learning Objective for Light Sources: Light travelling to the eye.Level 1We use our eyes to see with. We cannot see very well in the dark.What do we use to see with?When can we not see very well?

Level 2

Ask questions about light sources Ask questions about dull and shiny surfaces Sort things into groups depending upon how reflective they are Sort things into groups depending upon how bright they are. Describe what we can see in the light in the dark.

Some light must be there to see. The brighter the sun the more light there is. Some things give out more light than others. Language: shiny, dull, reflect. Why do you think we cannot see in the dark? How do you think we can group these materials: glass mirror, plastic sheets, felt, card, paper, metal strips etc.

Level 3 Predict what might happen when light is shone onto different surfaces

Objects look dark when there is not light falling on them. You can use a mirror or any shiny surface to reflect light.The shinier it is the better it reflects. What do you think might happen if we shine a light onto these different surfacesWhat do you think we can you use to reflect light?

Level 4

Record (draw/write) how light travels from the source to the eye Link smoothness of a surface with how well it reflects

Light travels in straight lines unless it hits an object (like a mirror), or passes onto a new material (like a lens).All surfaces reflect light but some do it better than others. The smoother the surface the better it is at reflecting. We see lightning before

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DRAFThearing the thunder because sound travels much more slowly than light.Why do you think we cannot see around corners? What do you think we can use to see around corners?What surfaces do you think make the best reflectors? Why do you think we can see lightning before you hear the thunder?How do you think light travels to our eyes from the thing we are seeing?Level 5 Explain how we can see Record (draw/diagram) an explanation of how we see colour Link what you know about reflection and how we see colour Model how a smooth surface reflects light and how a rough surface reflects lightLight is reflected off all surfaces and if it then passes into my eye I will see the object’s surface; some objects reflect only certain colours and so they appear coloured. The actual colour they appear depends on the light colours of red, green & blue that is being reflected. Blue objects reflect only the blue light. Why do you think some things appear red and others blue?

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LOWER C Exploring shadowsHow we use evidence Take children out to the playground to look at shadows on a sunny day. Emphasise that they will be looking for evidence- what is really happening not what they think is happening. Talk about the difference between opinion and evidence and how it relates to this activity.When are they long? When are they short? Does the time of day make any difference? Can the children make a thin shadow or a fat shadow? Can their shadow shake hands with a partner’s shadow without actually touching each other’s hands? Can they explain their findings?

Investigate – What makes a difference to a shadow? Possible ideas might be: size of object, distance from light source, material object is made from, angle of light source, strength of light source.

Explore ways in which the shadow of the figure can be made to change. Ask children to suggest questions they could investigate e.g. What happens to the size of the shadow when you move the figure nearer the light? Help children to decide how to carry out the investigation, including deciding on the measurements they are going to take. Ask children to record results and help them to present them in a line graph. Talk with children about patterns in the results and, if necessary, encourage them to repeat measurements to check them. (see investigation on shadows)

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UPPER C Exploring shadowsInvestigate – what makes a difference to how well you can see a shadow puppet? Possible ideas might be: distance from light source, type of light source, material of puppet, colour of material, angle of light, size of puppet (see investigation sheet on shadows)

Communicating scientific ideas On a sunny day, children could investigate their shadows in the playground. Ask them to draw round their shadow. What do you think will happen to their shadow if they draw round it again an hour later, standing in the same place? What do they notice about their new shadow? Why has it moved? Why has the length changed? Ask them to draw round their shadow every hour (use different coloured chalk each time). Ask them to predict each time the length and position of their shadow. Can they explain their findings? Why does their shadow move?To apply their knowledge, ask children to complete pictures, e.g. drawing of a child on a beach on a summer’s day. It is midday and the sun was at sunrise. Can they draw in where it will be at sunset? Give the children a picture of a child and its shadow with the sun low in the sky. Can they draw in the shadow and sun for midday? 3 o’clock in the afternoon etc.?

Use models to help us explain things Show children a sundial. How do they think it works? Using books, can they find out about how people in the past used the sun to tell the time? Children could go on to make their own sundial. Find pictures of objects and shadows in magazines and books. What can the children tell from the shadows about the position the sun and time of day? Encourage children to discuss their ideas in groups.Investigation: What makes a difference to a shadow made by the sun? Possible ideas might be: position of sun, time of year, brightness of sun, size of object

Investigation: Why do footballers have more than one shadow when playing a floodlit game? Let the children investigate with torches and play people e.g. Lego. How many shadows can they make for one person?

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UPPER – C Exploring shadowsGenerate ideas - Make a collection of objects and materials. Some of the objects or materials will not let the light through (opaque), some will let the light through but an image cannot be seen through them (translucent) and some will be clear (transparent), e.g. glass, perspex, polythene, plastic, wood, china, paper, card. Ask the children to sort the objects and materials into groups according to the three properties – transparent, translucent and opaque. Ask them to explain their groupings using the correct scientific vocabulary. Can they find other examples of everyday life of things that are transparent, translucent and opaque? Some papers, such as tracing paper, need to be transparent. Writing paper needs to be opaque. Ask the children to sort a collection of papers into opaque and transparent. They could test this out using newspaper with bold black print. Can they see the print through each paper? Can they see through some papers more easily than others? Try using two, then three, four or more sheets. Can the print still be seen? Can they grade the paper by degrees of transparency? Try the test again holding the newspaper against a window. Are there any other opaque papers now transparent? Can they explain their findings?

Investigate – what affects whether a material will let light through? Possible ideas might be: thickness of material, type of material, strength of light source, colour of materials.

Ask the children to investigate which types of papers, (e.g. greaseproof) would be suitable for a shadow puppet theatre screen. Why do they think, for example, that greaseproof paper is good for a screen? Can they find other materials which would be suitable?

Communicating scientific ideas - On a sunny day, ask children to place an upright object on the playground. They can mark hourly the length of the shadow made by the object. Can they predict when they will see the shortest shadow? The longest shadow? Can they explain why the shadow moves? Can they use the shadow clock to tell when lunchtime is? What makes the shadow?If records are kept, the above exercise can be repeated at different times of the year to compare shadows made by objects on the ground and relate them to the sun’s position in the sky at different seasons. The information could be put into an appropriate database for future use. If the children record the ‘path’ of the sun on a prepared picture during the day, can they explain why the sun changes position?

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UPPER – C Exploring shadowsUse models to help us explain things - link with Earth & Beyond (day and night) Use a globe and light source to demonstrate seasons and seasonal change (day length). Place a small card person with Blutack to the map of Britain on a globe and ask the children to turn the globe and observe when it becomes dark and light for the ‘mini person’. Tilt the North Pole towards the light source (sun) (summer in the Northern Hemisphere). Turn the Earth slowly and steadily just once to represent one day. Ask the children is the time in daylight longer or shorter than in darkness? Tilt the South Pole towards the light source (winter in the Northern Hemisphere). Again, turn the globe to represent one day. Is the time in daylight longer or shorter than in darkness? Discuss their observations. What did they discover about the day and night lengths? At midday in winter, is the sun high overhead or is it low in the sky? Can the children think how this will affect shadows in winter and summer? Children could further explore this idea using a torch and mini-person and holding the torch high (for summer) and low (for winter), observing the shadows that are made. Give the children a drawing showing the position of the sun in the sky and some objects, e.g. tree, flowers, person, etc. and ask the children to draw in the shadows.

Generate ideas Ask the children to record the path of the sun on a south-facing window during the day, marking the sun’s position with tape. Discuss the positions and ask children to predict where the tape might be for wintertime. How would this affect the shadows made? This activity could be repeated on other seasons to see how much lower or higher the sun appears in the sky.

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The idea I am finding more about is: light: making shadows. What variables do you think will affect a shadow?

Outcome: what we might observe or measure

Variables involved

Variable to be investigated

Variables to be kept the same

Question to ask Prediction (with reason

How dark the shadow is (scale 1 to 10)

Size of torch (brightness of light)

What do you think might happen to the

if we change the

We think if you change the

What might happen to

Is

because

How tall the shadow is (cm or mm)

Distance from material making shadow

Material that makes the shadow

How dark the roomAngle at which we shine the light from the torch at the material

Size of the solid chocolate left (cm or cm3)

Amount of chocolate (g or squares)Temperature of where we put the chocolate (C)

Wrapping around chocolate

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Exploring shadows C

Level 2 Ask questions about shadows; why/what/how do you think … Sort materials into those which make shadows and those which don’t.

I can see in the light and not in the dark. Some light must be there to see. Some materials make shadows. Shadows need light to be made. Language: dark, light, darker, lighter.What do you think we need to make a shadow?How do you think we can make the darkest shadow?

Level 3 Link the formation of a shadow with light not getting through the material Predict which material might make the darkest shadow

That some materials let light through them; while others let a little through and some let none through. Objects look dark when there is no light falling on themWhat material do you think might let light through/ let none through/ let a little through?What do you think we mean when we say ‘the best’ shadow?Why do you think some objects leave good shadows and other objects poor shadows?Why do you think different materials make different shadows? (clear plastic ruler, pencil, wooden ruler, cling film, tracing paper, etc.)

Level 4 Apply the words transparent, translucent and opaque when describing different materials Link the properties of the material to the shadow it makes Explain what a shadow is Record (draw) an explanation of how a shadow is formed

shadows are an area of less light due to a material preventing light from getting throughOpaque materials absorb light – it cannot pass through them. .How do you think we can find out which material might make the darkest shadow?What other factors might affect the darkness of a shadow?

Level 5 Explain how we see (in relation to the path light takes from the source to the eye)

Light is reflected off all surfaces and if it then passes into my eye I will see the object’s surface. Explain how we can make a shadow darker without changing the material

The intensity of a shadow varies depending on the intensity of the light and transparency of the material.Explain how we see things using the words: source, reflect, light, straight, eyes. How do you think we can make a shadow darker or lighter?

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