6 Magnetism
1 Why is a lodestone called a magnet?
For questions 2–6, circle the correct answer.
2 Magnet X can hold two steel nails while Magnet Y can hold four. All six nails are identical.
Which is the stronger magnet?
a) Magnet X
c) They are equally strong
b) Magnet Y
d) More information is needed
3 Which of these pairs of metals are both attracted by a magnet?
a) Iron and steel
c) Copper and lead
b) Gold and silver
d) Aluminium and zinc
4 A magnet that never loses its magnetism is:
a) lifelong
c) permanent
5 When magnets repel each other, they:
a) lose their magnetism
b) move towards each other
c) move away from each other
d) swing around.
b) energising
d) temporary.
6 How will these two magnets react when they are brought closer to each other? NS NS
a) Attract each other
c) No reaction
b) Repel each other
d) Swing around
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[5]
7 The diagram below shows the magnetic field of a single magnet.
Draw the magnetic fields for the following pairs of magnets.
a)
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NS
NS NS
NS N S
b)
6 Magnetism (cont.)
8 Use the clues below to help find the words in this wordsearch.
a) The poles of a bar magnet are and .
b) When iron filings are attracted by a magnet they form a pattern.
c) The force of a magnet is strongest at the
d) Like poles each other and unlike poles each other.
e) Big distances the effect of a magnet.
f) A naturally occurring magnet is a .
g) Magnets will pick up objects made of .
h) A magnetised needle that rotates to show direction is called a .
i) A compass always points north.
j) magnets never lose their power.
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EATTRACTOU LCOMPASSII DKCTNEKAEW EHTUOSIRON ELODESTONE NVMBSELOPY UEMAGNETIC LEPERDLEIF TNENAMREPI KCJNORTHEZ
[13]
9 This diagram shows Oersted’s experiment with a compass and part of an electrical circuit.
When the circuit is closed, what will happen to the compass needle?
10 What is an electromagnet?
For questions 11–16, circle the correct answer.
11 As the current in the wire increases, the strength of the magnetic field:
a) increases
c) stops the field
12 A relay is used to:
a) ring an electric bell
c) start a car ignition
b) remains unchanged
d) decreases.
b) spin a fan
d) heat an iron.
13 The feature that makes an electromagnet useful in a scrapyard is that:
a) it can be turned off and on
b) it cannot be turned off and on
c) it is weaker than a permanent magnet
d) it is stronger than a permanent magnet.
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switch compass battery
[1]
[1]
1Light
1 Light travels in straight lines called rays. In the space below, draw a ray of light.
2 A bundle of rays may travel as beams in three different arrangements as shown below. Identify each bundle. BEAMTYPE
a)
b) c)
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[3] 7 Light
3 What type of materials are:
a) luminous?
b) non-luminous?
4 Indicate whether each object below is luminous or non-luminous.
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[1]
[1]
a)b) c)d) e)f) [6] 7
(cont.)
Light
5 Each of the objects in question 4 emits either hot light or cold light. Write the letter of each object in the correct category below.
i) hot light
ii) cold light
6 In the table below, give the state of each object and say whether it is transparent (TP), translucent (TL) or opaque (O).
OBJECTSTATETP/TL/O
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a) b) c) d) e) f) [6]
7 What happens to light rays when they fall on the following types of objects?
a) Transparent objects
b) Translucent objects
c) Opaque objects
8 The diagram shows an activity involving a cylinder and a lamb. Various features of the activity have been labelled with a letter. Write the name of each feature identified by a letter.
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[3]
A B C D F E A B C D E F [6] 7 Light (cont.)
