Question
Which row links the property of a metal to its use?
▶️Answer/Explanation
Ans:
D
Metals have a high ductility, which is the ability to undergo plastic deformation without losing their strength. Ductility is an essential property for electrical wire materials since wires need to be flexible and easily shaped to fit various applications.
Question
Which row describes two uses of the named steel?
▶️Answer/Explanation
Ans:C
Stainless steel is a popular material for making cutlery, such as knives, forks, and spoons, for several reasons:
Corrosion resistance: Stainless steel contains chromium, which forms a thin, passive oxide layer on its surface when exposed to oxygen. This oxide layer provides excellent corrosion resistance, making the cutlery less susceptible to rusting and staining.
Hygiene: Stainless steel is non-porous and easy to clean, making it a hygienic choice for cutlery, particularly in foodservice and home settings.
Durability: Stainless steel cutlery is known for its strength and durability. It can withstand regular use, cleaning, and exposure to various foods without losing its shape or integrity.
Aesthetics: Stainless steel has a shiny and polished appearance that adds to the aesthetic appeal of cutlery.
Stainless steel is extensively used in chemical plants due to its resistance to chemical corrosion and its ability to maintain structural integrity in harsh environments.
Question
What is the symbol of the metal used in the manufacture of aircraft because of its strength and low density?
A Al B Cu C Fe D Zn
▶️Answer/Explanation
Ans:A
The metal that is commonly used in the manufacture of aircraft due to its strength and low density is aluminum(Al).
Question
Which row describes a use of the metal and explains why it is used?
▶️Answer/Explanation
Ans: C
Copper is commonly used in cooking utensils because of its excellent heat-conducting properties. Copper is one of the best thermal conductors among metals, which means it efficiently distributes and transfers heat across its surface. This property makes copper ideal for cooking applications where precise and even heat distribution is desired.
Question
Steel core aluminium cables are used for overhead electricity cables.
Which statement explains why these cables are used?
A Aluminium conducts electricity only when it surrounds a steel core.
B Aluminium conducts electricity and the steel core makes the cable stronger.
C Steel conducts electricity and is surrounded by aluminium because aluminium is an insulator.
D Steel conducts electricity and is surrounded by aluminium to stop the steel from corroding.
▶️Answer/Explanation
Ans: B
By combining the advantages of both aluminum and steel, overhead electricity cables can achieve a balance between electrical efficiency and mechanical integrity. The lightweight and conductive aluminum carry the electrical current, while the robust steel core provides support and structural strength to ensure the cable can span long distances between transmission towers without breaking or deforming excessively.