4. metal معدن
properties خـــواص
tough صلب
toughness صالبـــة
flexible مرن
flexibility مرونـــة
heavy ثقيل
heaviness ثقل
hard صلب
hardness صالبة
light خفيف
lightness خفـــة
strong قوي
5. Properties of materials المواد خواص
1- Glass is easy to break. الكسر سهل الزجاج
2- Rubber is a flexible material . =
Rubber has flexibility مرنة مادة المطاط
3- Concrete is strong in compression .
عند قوية مادة الخرسانةالضغط
4- Iron rusts easily . يصدأ الحديدبسهولة
5- Gold is malleable . للطرق قابل الذهب
6- Paper is easy to burn. االشتعال سهل الورق
6. Note the following examples:-
1- Concrete has compressive strength. When
it is pressed , it can't be broken or bent.
2- Copper is ductile. When you pull it, it can
be stretched , but it cannot be broken.
3-Nylon is tensile. When you pull it, it
stretches, but it doesn't break.
4- Gold is malleable, When you strike it with a
hammer , it changes it's shape , but it
doesn't break.
7. - Fibreglass is used for making boat hulls because it is
tough.
- Fibreglass is used for making boat hulls because of (
due to – owing to )its toughness. ( being tough )
- Glass is used for making windows because it is
transparent.
Glass is used for making windows because of ( due to –
owing to )its transparency
8. 1 - Glass can be broken easily
.الزجاج
يمكنأنيكسربسهولة
2 - Glass is used for windows
because it is transparent .
الزجاجيستخدمفيالشبابيكألنهشفاف
9. First of all, I want to mention the first part, part a. This is the hull of the
boat. The hull is usually made of fibreglass. This material, fibreglass, is used
because fibreglass is a very hard material. It cannot be cut or scratched
easily by rocks in the sea.
Secondly, I want to mention the second part, part b. This is the rudder.
The rudder is often made of wood. This material, wood, is used because it
doesn’t rust easily.
The third part, part c, is the sail. The sail is often made of polyester. This
is because polyester has great resistance to water. If it falls into the sea, it
does not absorb water, so it is easy to pull out of the water.
The final part which I want to mention is part d. This is the mast. The
mast of a boat is usually made of aluminium. This material, aluminium, is
used because it is very light. The sailor can carry it to the boat easily.
10. Part Hull الهيكل
Material fiberglass
properties hardness
reason Difficult to be cut or scratched
Part Rudder الدفة
Material wood
properties Light - floats
reason Résistance to rust
11. Part Mast الصاري
Material aluminum
properties lightness
reason can be carried easily
Part Sail الشراع
Material polyster
properties Résistance to water
reason does not absorb water
13. 2- Choose the correct answer from a, b, c or d:
1- Glass is easy …………….
a) break b) to break c) breaking d) broken
2- Windsurf boards are made of plastic foam, as this material is impossible ……. .
a) to sink b) be sunk c) from sinking d) for sinking
3- Fibreg1ass is used for making boat hulls ………it is tough.
a) because b) because of c) owing to d) due to
4- Copper is normally used for making ………..because it is easy to stretch.
a) bridges b) cars c) wires d) windsurf boards
5- The windsurf board is made ………. plastic foam.
a)in b)up c)from d)of
6- The boom is made of aluminum ………is light but does not have flexibility.
a) who b) whom c) whose d) which
7- The ………… is used for pulling up the mast.
a) Iifejacket b) boom c) board d) rope
8- When fibreglass is struck from the side, it cannot be ……….
Break b) breaks c) broken d) breaking
14. Fill in the spaces with words from the list:
properties - copper -transparency - honest - Aluminium - Iifejacket)
1- My sister is ……… He never tells lies.
2- Glass has the property of ……….. .
3- A……… is used for saving a swimmer from sinking in the
water
4- All metals have different………… .
5- …………… is a metal which is used for making wires.
15. A B
1-A light material A) flexbility
2-A flexible material B)floats on water
3-If a material is tough C)bends easily
4-Rubber has D)it doesn't break
16. Fill in the spaces with word(s) from the list :
strong – lifejacket- tension – ductillity – ductile –
1-This metal has tensile strength . It is strong in
………….
2-This plastic foam is …………. It floats easily on
water
3-copper is very ………….
4-The …………. prevents the swimmer from sinking
17. fiberglass – iron – sunk – Glass – squeeze – stretch
1-when you …………. concrete , it does no break or bend
2-A windsurf board is made of plastic foam which
cannot be ………….
3-Copper is normally used fro making wires because it is
easy to ………….
4-A winsurf board is made of plastic foam covered with
………….
5-…………. Is easy to break .
