a
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2 Energy
Practice 2 Sometimes the form of energy changes when the energy is transferred. Look at the
pictures and fill in the table for each picture.
Picture
ABCDE
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What form of energy is transferred?
Where does the energy go to?
Does the form of energy change? If so, how?
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2.3
Energy changes
Challenge 3 Read the sentences and then answer the questions. Vikal’s classroom is cold and
dark in winter. Before Vikal starts writing in his workbook, he rubs his hands together. The
teacher switches on the light so the class can see the whiteboard better. The teacher shows the
class a video on her computer. At break Vikal eats a banana. He then plays football with his
friends until he hears the bell ring at the end of break.
a Why does Vikal rub his hands together?
b Draw an energy chain to show the energy change when he does this.
c Describe the energy change that makes the light work.
d Draw an energy chain to show the energy changes that happen in the teacher’s computer.
e Where does Vikal get energy from to play football?
Draw an energy chain of the energy changes that allow Vikal to kick the ball.
g Name the form of energy that tells Vikal that break has ended.
h Why is he able to hear the sound?
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2 Energy
2.4 Energy and living things Focus 1 The food chains below are not correct. Put the living things
in each food chain in the right order and rewrite each food chain. a snail
cabbage
duck
b bird
caterpillar
leaf
c lizard
corn
d melon
eagle
cat
locust
snake
mouse
Practice 2 Look at the pictures.
rabbit
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plant
eagle
rat
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2.4
Energy and living things
a Which living thing is a producer?
b What do we call consumers that eat only plants?
c Name the two consumers that eat plants.
d Which animals are predators?
e Which animals are prey for these predators?
Which animal could be an omnivore? Say why.
g Draw a food chain for a producer and a consumer from the picture.
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2 Energy
h Draw a food chain for a producer, a predator and prey from the picture.
Challenge 3 Look at the drawing of a food chain below.
grass
deer
a Why is the grass plant at the start of the food chain?
b How does the grass get its food?
c What do the arrows in the food chain show?
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tiger
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2.4
Energy and living things
d Describe in your own words the information that the food chain drawing shows.
e In this food chain, will the organisms always be in the same order? Say why or why not.
4 Bears are omnivores that live in the same forests as tigers. a What is an omnivore?
b Add a bear to the food chain. Draw the new food chain.
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3 Materials 3.1 Materials, substances and particles Focus 1 Decide if each of the statements
below describes a solid or a liquid. Write the word ‘solid’ or liquid’ next to each statement. a It
has no fixed shape and can flow. b It has a fixed shape and cannot be squashed. c Its particles
move very little. d Its particles move around each other. e Its particles are quite close together. f
Its particles are very close together.
Practice 2 Imagine that you have 10 particles of matter. In the boxes, draw the arrangement of
the particles in: a a solid b a liquid.
a solid
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b liquid
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3.1
Materials, substances and particles
Choose words from the word box to complete the following sentences. You will not use all the
words and you will use some words twice. solids
liquids
loosely
shake
spread
shape
move
tightly
particles
All substances are made of
have a fixed
due to
packed
which
in
a fixed position. can
and take on the
of their container.
Challenge 4
The drawings show how scientists think the particles are arranged in a solid and a liquid.
Aa
Identify which drawing shows a solid and which drawing shows a liquid. A B
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3 Materials
b Write two sentences about how the particles are arranged in drawing A.
c Write two sentences about how the particles are arranged in drawing B.
5 Draw a line to match the correct ending to each of the sentence starter below. Sentence
starters:
Endings: their particles can move quickly in all directions.
a Solids have a fixed shape because … b Liquids can change shape in some ways because …
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their particles do not move very much.
their particles can move around each other.
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3.2
How do solids and liquids behave?
3.2 How do solids and liquids behave? Focus 1
Arun wants to show his sister that water can change shape. He chooses three different shaped
containers.
He pours 250 ml water into each container. a
Draw a line or lines onto each container to show where the water comes to when Arun pours it.
Colour in the water.
b Why did Arun pour the same amount of water into each container?
Complete these sentences to explain why the water changes shape when poured into the
different containers. Use the words in the box.
slide
Particles in a
shape
liquid
are close together, but they can past each other and change places.
Because of this liquids can change
easily.
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3 Materials
Can Arun do the same demonstration with wood?
b
Complete these sentences to explain your answer. Use the words in the box. shape
closely
positions
Particles in a solid are packed . They cannot change
together in fixed easily.
Practice
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Use the particle model to explain the difference in behaviour of solids and liquids.
Sand is a solid. a
In what way does sand behave like a liquid?
Why is sand able to behave like a liquid?
Think of two more examples of solids that appear to behave like liquids.
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3.2
How do solids and liquids behave?
Challenge 6 Class 4 investigated how much time it took for different volumes of sand to flow
through a funnel from one beaker into another beaker. These are their results. Volume of sand
in ml
Time taken for sand to flow in minutes
50
1
100
250
