1
Life cycles of
ǜoDžeƑiŠij ƎlîŠƥs
ǧȦǧ GloDžeƑiŠij îŠē ŠoŠȹfloDžeƑiŠij
ƎlîŠƥs
Focus
1
2
LooŒ îƥ ƥĺe ƎicƥƭƑes of ƎlîŠƥsȦ Øĺicĺ ƎlîŠƥs îƑe ǜoDžeƑiŠij ƎlîŠƥs
îŠē Džĺicĺ ƎlîŠƥs îƑe ŠoŠȹǜoDžeƑiŠij ƎlîŠƥsȧ ØƑiƥe ɃǜoDžeƑiŠijɄ oƑ
ɃŠoŠȹǜoDžeƑiŠijɄ iŠ ƥĺe sƎîce ċeloDž eîcĺ ƎicƥƭƑeȦ
1.1GŕūDžĚƑĿŠijîŠēŠūŠȹǜūDžĚƑĿŠijƎŕîŠƥƙ
2
¹ĺe ēiîijƑîŞ sĺoDžs ƥĺe life cycle of î ǜoDžeƑiŠij ƎlîŠƥ.
Àse ƥĺe DžoƑēs iŠ ƥĺe ċoNJ ƥo ĺelƎ yoƭ lîċel ƥĺe ēiîijƑîŞ.
ǜoDžeƑ
ŠeDž ƎlîŠƥ
seeēs
fƑƭiƥ
Practice
3
TēeŠƥify îŠē coloƭƑ iŠ ƥĺe ēiffeƑeŠƥ ƎîƑƥs of ƥĺe ǜoDžeƑ.
Àse ƥĺese coloƭƑsȠ
• ijƑeeŠ ȶ seƎîls
• ċlƭe ȶ Ǝeƥîls
• oƑîŠije ȶ îŠƥĺeƑ
• ċlîcŒ ȶ filîŞeŠƥ
• yelloDž ȶ sƥiijŞî
• ċƑoDžŠ ȶ oDŽîƑy
3
1gĿIJĚČNjČŕĚƙūIJǜūDžĚƑĿŠijƎŕîŠƥƙ
4
¹ĺese seŠƥeŠces ēescƑiċe ƥĺe ēiffeƑeŠƥ ƎîƑƥs of î ǜoDžeƑ îŠē ƥĺeiƑ fƭŠcƥioŠs.
Àse ƥĺe DžoƑēs iŠ ƥĺe ċoNJ ƥo fill iŠ ƥĺe sƎîces ċeloDž.
sƥiijŞî
¹ĺe
oDŽîƑy
Ǝeƥîls
îŠƥĺeƑs
¹ĺey ŞîŒe
cîƑƎel
.
iŠ ƥĺeiƑ ƥiƎsȡ Džĺicĺ îƑe cîlleē
¹ĺe feŞîle ƎîƑƥ of ƥĺe floDžeƑ is ƥĺe
Challenge
LooŒ îƥ ƥĺe ēƑîDžiŠij of î ǜoDžeƑ.
.
. Tƥ is Şîēe ƭƎ
ȡ Džĺicĺ collecƥs ƎolleŠȡ îŠē ƥĺe
Džĺicĺ coŠƥîiŠs ƥĺe eijijs.
4
ƎolleŠ
ofƥeŠ ĺîDŽe ċƑiijĺƥ coloƭƑs ƥo îƥƥƑîcƥ iŠsecƥs.
¹ĺe Şîle ƎîƑƥs of ƥĺe floDžeƑ îƑe ƥĺe
of ƥĺe
sƥîŞeŠs
ȡ
1.1GŕūDžĚƑĿŠijîŠēŠūŠȹǜūDžĚƑĿŠijƎŕîŠƥƙ
5
ØƑiƥe lîċels oŠ ƥĺe ēƑîDžiŠij foƑ ƎîƑƥs ȡ ȡ
6
a Øĺicĺ ƎîƑƥ of ƥĺe floDžeƑ is ŞissiŠijȧ
îŠē '.
b ēē ƥĺe ŞissiŠij ƎîƑƥ ƥo ƥĺe ēƑîDžiŠij.
7
Øĺîƥ coloƭƑ Džoƭlē yoƭ eNJƎecƥ ƥĺe folloDžiŠij ƎîƑƥs ƥo ċeȧ /NJƎlîiŠ yoƭƑ îŠsDžeƑs.
a ¡îƑƥ b ¡îƑƥ '
5
1gĿIJĚČNjČŕĚƙūIJǜūDžĚƑĿŠijƎŕîŠƥƙ
1.2 ¡olliŠîƥioŠȡ fƑƭiƥs îŠē seeēs
Focus
1
Àse ƥĺe DžoƑēs iŠ ƥĺe ċoNJ ƥo coŞƎleƥe ƥĺe seŠƥeŠces îċoƭƥ ƎolliŠîƥioŠ
îŠē fƑƭiƥ îŠē seeē foƑŞîƥioŠ. Þoƭ Džill ƭse soŞe DžoƑēs ŞoƑe ƥĺîŠ oŠce.
DžiŠē
iŠsecƥs
seeēs
îŠƥĺeƑs
a ¹ĺe
ŠecƥîƑ
eijijs
oDŽîƑy
ƎolleŠ
sƥiijŞî
feƑƥilisîƥioŠ
of floDžeƑs ŞîŒe î yelloDž ƎoDžēeƑ. ¹ĺis is cîlleē
b ¡olliŠîƥioŠ ĺîƎƎeŠs DžĺeŠ ƎolleŠ ŞoDŽes fƑoŞ ƥĺe
.
ƥo ƥĺe
of î floDžeƑ of ƥĺe sîŞe ƥyƎe.
c ¬oŞe ƎlîŠƥs ƭse
d
ƥo ċloDž ƥĺe ƎolleŠ fîƑ îDžîy.
DŽisiƥ floDžeƑs ƥo feeē oŠ
oŠ ƥĺeiƑ ċoēies îƥ ƥĺe sîŞe ƥiŞe.
e ¹ĺe ƎolleŠ îŠē
ŏoiŠ ƥoijeƥĺeƑ. ¹ĺis ĺîƎƎeŠs iŠsiēe ƥĺe
ēƭƑiŠij
f ¹ĺe
. ¹ĺey ijeƥ
. ¹ĺis is ĺoDž
foƑŞ.
ċecoŞes ƥĺe fƑƭiƥ.
Practice
liyîĺɄs clîss iŠDŽesƥiijîƥeē î scieŠƥiǛc ƐƭesƥioŠ. ¹ĺese îƑe ƥĺeiƑ Ƒesƭlƥs.
6
ColouroIJǜoDžer
Number of insects
that DŽisiteē ǜoDžer
¤eē
3
ÞelloDž
12
Øĺiƥe
10
lƭe
6
TŠČĿēĚŠƥîŕĿŞîijĚūIJîŠ
ĿŠƙĚČƥƥūċĚƙƭƎƎŕĿĚē
1.2¡ūŕŕĿŠîƥĿūŠȡIJƑƭĿƥƙîŠēƙĚĚēƙ
2
a ¬ƭijijesƥ ƥĺe ƐƭesƥioŠ ƥĺîƥ liyîĺɄs clîss iŠDŽesƥiijîƥeē.
b TēeŠƥify ƥĺe ƥyƎe of scieŠƥific eŠƐƭiƑy ƥĺey ƭseē iŠ ƥĺeiƑ iŠDŽesƥiijîƥioŠ.
ĺoose fƑoŞ ƥĺe folloDžiŠij ƥyƎesȠ fîiƑ ƥesƥiŠijȡ ƑeseîƑcĺȡ oċseƑDŽiŠij oDŽeƑ ƥiŞeȡ
iēeŠƥifyiŠij îŠē clîssifyiŠijȡ looŒiŠij foƑ ƎîƥƥeƑŠs.
3
'ƑîDž î ċîƑ cĺîƑƥ of ƥĺe Ƒesƭlƥs. Àse î ēiffeƑeŠƥ coloƭƑ foƑ eîcĺ ċîƑ.
4
a Øĺicĺ coloƭƑ floDžeƑ ēiē ƥĺe Şosƥ iŠsecƥs DŽisiƥȧ
b Øĺicĺ coloƭƑ floDžeƑ ēiē ƥĺe feDžesƥ iŠsecƥs DŽisiƥȧ
¬ƭijijesƥ î ƑeîsoŠ foƑ yoƭƑ îŠsDžeƑ.
5
a Øĺîƥ coŠclƭsioŠ cîŠ yoƭ ŞîŒe fƑoŞ ƥĺese Ƒesƭlƥsȧ
7
1gĿIJĚČNjČŕĚƙūIJǜūDžĚƑĿŠijƎŕîŠƥƙ
b Øĺîƥ cîŠ yoƭ ēo ƥo ċe sƭƑe yoƭƑ coŠclƭsioŠ is coƑƑecƥȧ
Challenge
¬oŞe ŒiŠēs of ǜoDžeƑs ĺîDŽe Şîle ƎîƑƥs oƑ feŞîle ƎîƑƥs oŠly.
¹ĺe ǜoDžeƑs sĺoDžŠ iŠ ƥĺe ēƑîDžiŠijs oŠly ĺîDŽe Şîle oƑ feŞîle ƎîƑƥs.
A
8
B
6
Øĺicĺ is ƥĺe Şîle ǜoDžeƑ îŠē Džĺicĺ is ƥĺe feŞîle ǜoDžeƑȧ ¬îy ĺoDž yoƭ ŒŠoDž.
7
'escƑiċe ƥĺe ƎƑocess of ƎolliŠîƥioŠ iŠ ǜoDžeƑs liŒe ƥĺese.
8
'ƑîDž îƑƑoDžs oŠ ƥĺe ēƑîDžiŠijs ƥo sĺoDž ĺoDž ƎolliŠîƥioŠ ĺîƎƎeŠs.
1.3OūDžƙĚĚēƙîƑĚƙƎƑĚîē
1.3 OoDž seeēs îƑe sƎƑeîē
Focus
1
Øĺîƥ ēo Dže cîll ƥĺe sƎƑeîēiŠij of seeēs îDžîy fƑoŞ ƥĺe ƎîƑeŠƥ ƎlîŠƥȧ
2
OoDž îƑe ƥĺese seeēs sƎƑeîēȧ ¬oƑƥ ƥĺeŞ iŠƥo ijƑoƭƎs îŠē DžƑiƥe ƥĺe ŠîŞes
of ƥĺe seeēs iŠ ƥĺe ƥîċle.
acacia
impatiens
sycamore
dandelion
plum
Eaten
coconut
mangrove
Stick on
FlNj aDžaNj
lantana
jacaranda
Float
blackjack
Explode
9
1gĿIJĚČNjČŕĚƙūIJǜūDžĚƑĿŠijƎŕîŠƥƙ
Practice
3
10
qîƥcĺ ƥĺe Džîy seeēs îƑe sƎƑeîē iŠ ƥĺe ǛƑsƥ colƭŞŠ Džiƥĺ ƥĺe ēescƑiƎƥioŠ of ĺoDž
ƥĺe seeē oƑ fƑƭiƥ is îēîƎƥeē ƥo ƥĺe Džîy iƥ is sƎƑeîē iŠ ƥĺe secoŠē colƭŞŠ.
'ƑîDž î liŠe fƑoŞ ƥĺe Džîy ƥĺe seeē is sƎƑeîē ƥo ƥĺe ēescƑiƎƥioŠ of ƥĺe seeē oƑ fƑƭiƥ.
Way seed is spread
OoDž seed or fruit is adapted to the Džay it is spread
y DžîƥeƑ
¬eeē ĺîs sƎiŠes îŠē ĺooŒs
y DžiŠē
¬eeē Ǝoēs ēƑy oƭƥ îŠē ċƭƑsƥ oƎeŠ
y îŠiŞîls
¬eeē ĺîs sƎoŠijy coDŽeƑiŠij ƥĺîƥ ĺelƎs iƥ ǜoîƥ
y eNJƎlosioŠ
¬eeē is DŽeƑy liijĺƥ Džiƥĺ ƥĺiŠ ƎîƎeƑy DžiŠijs
4
'escƑiċe îŠoƥĺeƑ Džîy iŠ Džĺicĺ ƎlîŠƥs îƑe îēîƎƥeē ƥo seeē ēisƎeƑsîl ċy îŠiŞîls.
HiDŽe îŠ eNJîŞƎle.
5
Øĺy Şƭsƥ seeēs ċe sƎƑeîēȧ
1.3OūDžƙĚĚēƙîƑĚƙƎƑĚîē
Challenge
ĺŞeē îŠē ÞîseeŠ iŠDŽesƥiijîƥeē seeē ēisƎeƑsîl. ¹ĺey collecƥeē ƥĺƑee
ēiffeƑeŠƥ seeēs. ¹ĺey ēƑoƎƎeē eîcĺ seeē ƥĺƑee ƥiŞes îŠē ŞeîsƭƑeē ĺoDž
loŠij iƥ sƥîyeē iŠ ƥĺe îiƑ eîcĺ ƥiŞe. ¹ĺese îƑe ƥĺeiƑ Ƒesƭlƥs.
Seed
Time in the
air Reading 1
Time in the
air Reading 2
Time in the
air Reading 3
Average time
in the air
9 secoŠēs
10 secoŠēs
11 secoŠēs
10 secoŠēs
20 secoŠēs
22 secoŠēs
24 secoŠēs
22 secoŠēs
15 secoŠēs
14 secoŠēs
7 secoŠēs
12 secoŠēs
¬eeē 1
sycamore
¬eeē 2
dandelion
¬eeē 3
helicopter
6
OoDž DžeƑe ƥĺe seeēs iŠ ƥĺe iŠDŽesƥiijîƥioŠ ēisƎeƑseēȧ
HiDŽe î ƑeîsoŠ foƑ yoƭƑ îŠsDžeƑ.
11
1gĿIJĚČNjČŕĚƙūIJǜūDžĚƑĿŠijƎŕîŠƥƙ
7
'ƑîDž î ijƑîƎĺ of ƥĺe îDŽeƑîije ƥiŞe eîcĺ seeē sƥîyeē iŠ ƥĺe îiƑ.
8
a Øĺicĺ seeē sƥîyeē iŠ ƥĺe îiƑ loŠijesƥȧ
b ¬ƭijijesƥ î ƑeîsoŠ foƑ ƥĺis.
12
1.4¬ĚĚēijĚƑŞĿŠîƥĿūŠ
9
a Øĺy ēiē ĺŞeē îŠē ÞîseeŠ ƑeƎeîƥ ƥĺeiƑ ŞeîsƭƑeŞeŠƥsȧ
b ~Še Ƒesƭlƥ is Ɛƭiƥe ēiffeƑeŠƥ ƥo ƥĺe oƥĺeƑs.
TēeŠƥify ƥĺe Ƒesƭlƥ îŠē sƭijijesƥ î ƑeîsoŠ foƑ iƥ.
10 ¬îy ĺoDž ĺŞeē îŠē ÞîseeŠ Şîēe ƥĺe iŠDŽesƥiijîƥioŠ î fîiƑ ƥesƥ.
1.4 ¬eeē ijeƑŞiŠîƥioŠ
Focus
1
qîƥcĺ eîcĺ DžoƑē îċoƭƥ ĺoDž seeēs ijƑoDž Džiƥĺ iƥs ēescƑiƎƥioŠ.
'ƑîDž î liŠe fƑoŞ ƥĺe DžoƑē ƥo iƥs ŞeîŠiŠij.
Word
Description
HeƑŞiŠîƥioŠ
¹ĺe ǛƑsƥ ƎîƑƥ ƥĺîƥ ijƑoDžs
ØîƥeƑ
Heƥs sŞîlleƑ
GiƑsƥ Ƒooƥ
ØĺeŠ î seeē sƥîƑƥs ƥo ijƑoDž
GiƑsƥ sĺooƥ
qîŒes ƥĺe seeē sDžell
¬eeē
HƑoDžs ƭƎDžîƑēs
13
1gĿIJĚČNjČŕĚƙūIJǜūDžĚƑĿŠijƎŕîŠƥƙ
2
14
¹ĺe ƎicƥƭƑes of ƥĺe sƥîijes of seeē ijeƑŞiŠîƥioŠ îƑe iŠ ƥĺe DžƑoŠij oƑēeƑ.
•
¹ĺe fiƑsƥ Ƒooƥ ijƑoDžs.
•
LeîDŽes ijeƥ ċiijijeƑ îŠē seeēs sĺƑiDŽel.
•
¹ĺe fiƑsƥ leîDŽes ijƑoDž.
•
¹ĺe seeē coîƥ sƎliƥs.
•
¹ĺe fiƑsƥ sĺooƥ ijƑoDžs.
1.4¬ĚĚēijĚƑŞĿŠîƥĿūŠ
Practice
lîss 5 iŠDŽesƥiijîƥeē ijeƑŞiŠîƥioŠ. ¹ĺey Ǝƭƥ seeēs oŠ ēîŞƎ coƥƥoŠ Džool îŠē
Ǝlîceē ƥĺeŞ iŠƥo Ǝlîsƥic ċîijs. ¹ĺey ƥĺeŠ Ǝƭƥ ƥĺe Ǝlîsƥic ċîijs iŠ ēiffeƑeŠƥ Ǝlîces.
¹ĺey cĺecŒeē ƥĺe seeēs îfƥeƑ ƥĺƑee ēîys. ¹ĺis is î ċîƑ cĺîƑƥ of ƥĺeiƑ Ƒesƭlƥs.
Number of seeds germinated
10
9
8
7
6
5
4
3
2
1
0
freezer
fridge
drawer
top of
desk
Place where seeds were put
3
TŠ Džĺicĺ Ǝlîce ēiē ƥĺe Şosƥ seeēs ijeƑŞiŠîƥeȧ
4
OoDž ŞîŠy seeēs ijeƑŞiŠîƥeē iŠ ƥĺe fƑeeǕeƑȧ
5
¬ƭijijesƥ î ƑeîsoŠ Džĺy ƥĺe sîŞe ŠƭŞċeƑ of seeēs ijeƑŞiŠîƥeē oŠ ƥĺe
ēesŒ ēƑîDžeƑ îŠē oŠ ƥĺe ƥoƎ of ƥĺe ēesŒ.
15
1gĿIJĚČNjČŕĚƙūIJǜūDžĚƑĿŠijƎŕîŠƥƙ
6
Øĺîƥ ēo ƥĺe Ƒesƭlƥs ƥell yoƭ îċoƭƥ ƥĺe coŠēiƥioŠs ƥĺîƥ seeēs Šeeē ƥo ijeƑŞiŠîƥeȧ
Challenge
ƑƭŠ ijeƑŞiŠîƥeē soŞe seeēs. Oe ŞeîsƭƑeē ƥĺe leŠijƥĺ of ƥĺe seeēliŠijs
eDŽeƑy ƥDžo ēîys. Oe DžƑoƥe ēoDžŠ ĺis ŞeîsƭƑeŞeŠƥsȠ
'îy 2Ƞ10 ŞŞȡ 'îy 4Ƞ15 ŞŞȡ 'îy 6Ƞ25 ŞŞȫ 'îy 8Ƞ35 ŞŞȡ 'îy 10Ƞ40 ŞŞ
¡ƑeseŠƥ ƑƭŠɄs Ƒesƭlƥs iŠ î ƥîċle. ¤eŞeŞċeƑ ƥo ijiDŽe eîcĺ colƭŞŠ î ĺeîēiŠij.
8
'ƑîDž î liŠe ijƑîƎĺ of ƑƭŠɄs Ƒesƭlƥs.
Length of seedlings
7
Days
16
1.4¬ĚĚēijĚƑŞĿŠîƥĿūŠ
9
a ØĺeƑe ēoes ƥĺe seeē ijeƥ ƥĺe eŠeƑijy iƥ Šeeēs foƑ ijeƑŞiŠîƥioŠȧ
b Øĺicĺ ƎîƑƥ of ƥĺe ijeƑŞiŠîƥiŠij seeē ijƑoDžs fiƑsƥȧ
c TŠ Džĺicĺ ēiƑecƥioŠ ēoes iƥ ijƑoDžȧ
d ¬ƭijijesƥ î ƑeîsoŠ foƑ ƥĺis.
10 sîŞe ƥDžo seeēs ƥĺîƥ Dže eîƥ.
17
2
Sound
2.1 How are sounds made?
Focus
Look at the drawing:
18
1
Complete this drawing to show what will happen if you tap gently
on the jar with a pencil. You will need to draw in the rice grains.
Label all parts of the drawing.
2
Complete this drawing to show what will happen if you tap hard on the
jar with a pencil. Label all the parts of the drawing.
2.1 How are sounds made?
3
Use the words in the box to complete the sentences.
vibrations
more
less
vibrate
a When you tap the jar it makes the rice grains
b
.
travel through the jar and plastic wrap to the rice.
c The rice grains move
when you tap the jar gently.
d The rice grains move
when you tap the jar hard.
Practice
Loudness of sounds in dB
èara and SoǛa listened to sounds through different materials.
This is the bar chart they drew to show how loud the sounds were.
Use the bar chart to answer the questions.
4
5
4
3
2
SEE WORD FILE
CONCERNING THIS
ILLUSTRATION…
1
0
solid
liquid
Materials
gas
Is the material through which the sound was loudest a solid, a liquid or a gas?
19
2 Sound
a Zara and Sofia also listened to sound through a woollen hat.
The loudness of the sound was 3.5dB.
Draw another bar on the bar chart to show this.
Loudness of sounds in dB
5
5
4
3
2
1
0
SEE WORD FILE
CONCERNING THIS
ILLUSTRATION…
solid
liquid
Materials
gas
b Is wool a solid, a liquid or a gas?
6
Which kinds of materials on the bar chart do sounds travel through best?
Challenge
Zara and SoǛa investigated how well sound travels through different materials.
They listened to the sound of a clock ticking through the materials to see
how loud it was. These are their results:
20
Material
Distance from clock
Loudness of sound
Plastic
0 cm
Wood
0 cm
Water
2 cm
Air
0 cm
Cardboard
5 cm
2.1 How are sounds made?
7
Identify the control, independent and dependent variables.
8
Which material did sound travel through best?
9
Which material(s) did sound travel through worst?
10 Do you think Zara and SoǛaɄs results are accurate? /xplain why or why not.
11 What should Zara and SoǛa do to get accurate results?
21
2 Sound
2.2 Volume and pitch
Focus
1
Draw a line from each of the sounds shown on the drawings to match its volume.
SEE WORD FILE
CONCERNING THIS
ILLUSTRATION…
22
2
What unit is the volume measured in on the drawing?
3
Which of the sounds shown do you think has the highest pitch?
2.2 Volume and pitch
4
How loud do you think a Formula 1 racing car is?
Is it softer than, the same as or louder than the sounds A, B and C below?
A
B
A is
a formula 1 racing car.
B is
a formula 1 racing car.
C is
a formula 1 racing car.
C
Practice
Marcus and his friends used a rating system of ticks to record the volume
of sounds they heard during their lunch break. These are their results.
Sound
Loudness
Talking
Laughing
Shouting
Music playing
School bell ringing
SEE WORD FILE
CONCERNING THIS
ILLUSTRATION…
Incidental image cut out
image of a lunchbox to
be supplied
23
2 Sound
24
5
Draw a bar chart of the results. Remember to give your bar chart
a heading and clearly label the bars and the axes.
6
How could the boys have made more accurate measurements?
7
Identify the control, independent and dependent variables.
8
Which sound was the quietest?
2.2 Volume and pitch
9
How are the vibrations different as a sound gets quieter?
10 Describe how pitch vibrations are different to volume vibrations.
Challenge
Zara and SoǛa measured the sound volume of a clock ticking through
different materials. These are their results.
NOTE: Global
instructions state that
if there are numbers
and headings in a
table they are centred.
Material
Sound in dB
Water
45
Metal
65
Wood
60
Glass
50
Air
40
Incidental image
of clocks to be
supplied
SEE WORD FILE
CONCERNING THIS
ILLUSTRATION…
25
2 Sound
11 Draw a bar chart of the results.
12 a
Which material did sound travel through best?
b /xplain why sound travels well through this material.
13 Identify the control, independent and dependent variables in this investigation.
14 a
Write a conclusion based on the data.
b How could Zara ad Sofia make a more accurate conclusion?
26
2.3 Changing the volume of sound
2.3 Changing the volume of sound
Focus
1
What is volume of sound?
2
Give an example of a loud sound.
3
Give an example of a quiet sound.
4
How does the bell in the picture make a sound?
27
2 Sound
5
Suggest as many ways you can think of to make the sound of the bell ringing louder.
You can write or draw your ideas.
Practice
SEE WORD FILE
CONCERNING THIS
ILLUSTRATION…
6
28
a Which material did Sofia suggest to muffle the sound of the phone?
2.3 Changing the volume of sound
b List three other materials that Zara and Sofia could test.
7
Write down two other pieces of equipment and apparatus that they will need
to make it a fair test besides the materials to test and the mobile phone.
8
Name the control variable in their investigation.
/xplain why it is the control variable.
9
What is the independent variable in their investigation?
/xplain why it is the independent variable.
10 What is the dependent variable in their investigation?
/xplain why it is the dependent variable.
29
2 Sound
Challenge
11 Make a drawing to show how SoǛa could use a sheet of card to
make sounds louder.
12 /xplain how your idea will help SoǛa to hear sounds louder.
_______________________________________________________________________________
_______________________________________________________________________________
13 What could you do to improve your design so that it traps more sound
and directs the sound better into her ear?
_______________________________________________________________________________
_______________________________________________________________________________
_______________________________________________________________________________
30
2.4
Changing the pitch of sound
2.4 Changing the pitch of sound
Focus
Look at the picture of SoǛa playing the recorder.
SEE WORD FILE
CONCERNING THIS
ILLUSTRATION…
1
Complete the sentences about the pitch of the notes SoǛa plays.
Use the words in the box.
lower
longer
higher
slower
shorter
faster
vibrations
low
high
When Sofia covers fewer air holes with her fingers, it makes the column of air
in the recorder
. This makes the air vibrate
and gives the sound a
pitch.
When Sofia covers more holes with her fingers, it makes the column of air
. This makes the air vibrate
in the recorder become
and gives the sound a
The speed of the air
or
pitch.
changes the pitch. The pitch can be
.
31
2 Sound
Practice
Arun has made a guitar. Look at pictures A, B, C and D of ArunɄs guitar.
So far he has only put in one string. Suppose Arun presses on the string
at point X and then plucks the string between X and Y.
SEE WORD FILE
CONCERNING THIS
ILLUSTRATION…
2
What is pitch?
3
Will the pitch be highest when the string is plucked between X and Y
in drawing A, B, C or D? /xplain why.
4
How will the pitch of the sound change if the guitar string is thicker?
_______________________________________________________________________________
_______________________________________________________________________________
32
2.4
Changing the pitch of sound
Challenge
Zara made the musical instrument in the picture.
She Ǜlled some bottles with different amounts of water.
To play the instrument Zara blows across the tops of the bottles.
A
B
C
D
E
5
What type of musical instrument is this?
6
Which bottle, B, C or D, will produce the sound with the lowest pitch?
/xplain why.
33
2 Sound
7
Which bottle will produce the sound with the highest pitch? /xplain why.
8
Zara wants to put water in the empty bottles A and /.
a Draw the level of water she must pour into bottle A to make a lower pitch than B.
b Draw the level of water she must pour into bottle / to make a higher pitch than D.
34
2.4
9
Changing the pitch of sound
Look at the picture of a drum.
SEE WORD FILE
CONCERNING THIS
ILLUSTRATION…
How do you think you can change the pitch of the drum?
35
3
States and
properties of matter
3.1 Gases
Focus
Look at the picture of a glass of soda.
1
Write the labels for solid, liquid and gas in the correct places on the picture.
2
Use the words in the box to complete the sentences about the states of matter.
vinegar
oxygen
states
a Solids, liquids and gases are the three
b All matter is made of tiny
c
d A
e
36
particles
of matter.
ɇ.
is an example of a gas.
is an example of a solid.
is an example of a liquid.
rock
3.1 Gases
3
Air is a mixture of gases. Say why this is so.
Ɋ
Practice
4
You have particles of matter.
Draw the particles in each box below to represent a solid, a liquid and a gas.
Solid
5
Liquid
Gas
Fill in the table to describe how particles move in the different states of matter.
State of matter
Do particles move a lot,
quite a lot or hardly at all?
Do particles move apart, move
far apart or shake in one place?
Solid
Liquid
Gas
37
3 States and properties of matter
Challenge
Look at the pictures of particles in the two syringes, A and B.
6
plunger
open end A
plunger
open end B
a Which syringe do you think contains water and which syringe contains air?
b Explain your answer using the particle model.
7
38
If you hold your Ǜnger over the open end of the syringes, which plunger
will be easier to push down? Use the particle model to explain why.
3.2 Properties of water
3.2 Properties of water
Focus
Choose the correct answer to each of the questions.
Draw a circle around the letter of the correct answer to each question.
1
Which process makes ice become liquid on a hot day?
a freezing
b melting
c boiling
d cooling
2
Which answer shows the process of melting?
a liquid + heat
3
4
solid
b gas – heat
liquid
c solid + heat
liquid
d solid – heat
liquid
Which answer shows the process of boiling?
a liquid – heat
gas
b gas + heat
liquid
c liquid + heat
gas
d gas – heat
liquid
Which of the following does not happen when we freeze water?
a it solidifies
b it contracts
c it expands
d it changes state
39
3 States and properties of matter
5
Your teacher heats a pan of water. When the water temperature is ,
which point has the water reached?
a melting point
b freezing point
c cooking point
d boiling point
Practice
Arun put a block of ice on a saucer.
6
Make a drawing to show the ice cube after:
a two minutes
40
b 10 minutes
3.2 Properties of water
7
a What has happened to the ice?
b Why did this process happen?
8
a At what temperature does this process start to happen?
b What do we call this temperature?
Challenge
SoǛaɄs class investigated boiling. These are their results.
Liquid
Temperature at which
liquid boils (°C)
Pure water
100
Salty water
101
Milk
102
Sugar water
101
Tap water
101
41
3 States and properties of matter
9
What do we call the temperature at which a liquid boils?
10 a Which liquid boils at the highest temperature?
b At what temperature does pure water boil?
11 a Does water always boil at the same temperature? How do you know this?
b Use the results to suggest a reason for this.
12 Why canɄt you cook a hardȹboiled egg on Mount Everest?
You may have to do some research Ǜnd out.
Ɋ
42
3.3 Evaporation and condensation
3.3 Evaporation and condensation
Focus
1
Underline the correct words to complete these sentences:
Evaporation occurs when a liquid/gas changes into a gas/liquid. This happens
because the particles gain/lose heat and move faster/slower and closer together/
further apart until some of them escape from the surface and become
a liquid/gas. The opposite process to evaporation is boiling/condensation.
2
Decide if the sentences are true or false. Mark each one as either true or false .
True
False
a Evaporation makes wet clothes dry.
b Water disappears when it evaporates.
c Condensation occurs when a gas changes to a liquid.
d Heat makes condensation happen faster.
e Particles must lose energy before they can condense.
Practice
Zara left some cool drink in a bottle on a windowsill.
The next day she opened the bottle and saw
that the inside of the lid was wet and there were
droplets on the inside the bottle.
43
3 States and properties of matter
3
What liquid formed inside the lid and inside the bottle?
4
Where did the liquid come from?
5
Name the process that made the liquid form inside the lid.
6
Explain how this process made the liquid form.
7
a Which process is the reverse of the process you named in question number 5?
b Would the drops of liquid have formed without the reverse process?
Say why or why not.
44
3.3 Evaporation and condensation
Challenge
Marcus and Arun investigated the evaporation of water.
They placed two containers of water on the windowsill.
A
B
Here are their results.
Day
Volume of water in container (ml)
Container A
Container B
1
250
250
2
230
200
3
210
160
4
180
120
5
150
Ɇ80
6
7
45
3 States and properties of matter
Draw a graph of the results for each container of water.
Think about the type of graph you should draw.
Volume of water (ml)
8
Time (days)
9
a From which container did most water evaporate? Explain how you know this.
b Why do you think more water evaporated from that container?
10 Predict the results if Marcus and Arun continue their investigation for
another two days. Fill in your prediction in the table and add the new
points to your graph in another colour.
46
3.4 Solutions
3.4 Solutions
Focus
1
Arun is writing a report on an investigation. Help him complete his report.
Use the words in the box to help you.
salt
solute
evaporating
solvent
warm
dissolved
evaporation
solution
water
evaporated
Aim
by
We wanted to find out if you can get salt back from a
.
Method
some salt in water in a beaker to make a salt
We
. The salt was the
the
a few days.
and the water was
. We left the beaker in a
place for
Results
in the bottom of the container.
After a few days there was
There was no
. It had
.
Conclusion
back from a
We found that we can get
We do this by
.
the water.
47
3 States and properties of matter
Practice
SoǛa poured hot water into a glass. She added a teaspoon of coffee powder.
She stirred the water.
2
a Make a drawing of the glass of water and coffee before Sofia stirred it.
b Make a drawing of the glass of water and coffee after Sofia stirred it.
B
A
Before Sofia stirred
After Sofia stirred
c Write the labels ɃsoluteɄ, ɃsolventɄ and ɃsolutionɄ on your drawings.
3
Explain what happened to the coffee powder when SoǛa stirred the water.
Ɋ
4
How can SoǛa get the coffee powder back again?
Ɋ
Ɋ
48
3.4 Solutions
Challenge
Marcus put a teaspoonful of sugar into the glass of water to make a solution.
He stirred the mixture. After a while, the sugar disappeared.
5
a Where has the sugar gone?
b How can you test that the sugar is still there?
c What part of a solution is the water?
d What part of a solution is the sugar?
Water and sugar are made up of many tiny particles.
We can represent the particles of water and sugar in a model like this:
Particles of water
Particles of sugar
49
3 States and properties of matter
50
6
Use the particle model to draw a picture of the solution Marcus made.
Label your particles.
7
Marcus added more and more sugar to the solution until no more sugar dissolved.
Use the particle model to draw a picture of the solution.