#1
Primarily because of its lighter weight. Copper is a better conductor, but is too heavy and more expensive.
#2
Aluminium is lighter than most other metals yet still strong enough to carry its weight, so the cables do not need to be monstrously thick, and it is a fairly highly conductive material (being a metal) so power is not wasted on the transmission. It should be noted, however, that aluminum by itself is not normally used for long spans, i.e. high-voltage power transmission. It is wrapped around a steel core. The steel is used for strength, and the aluminum is used for better conductivity. Such cable is called type ACSR (short for aluminum conductor - steel reinforced).
#3
Because of its light weight. It is great at conducting a current and copper is expensive.
#4
Because of conductivity.
Window frames used to be made from steel but aluminium is lighter and does not rust.
Brass, aluminium, stainless steel, cast iron, wood, Bakelite, plastic and other materials have all been used to make door handles. The mechanism is usually made from brass, steel or stainless steel.
Yes, in fact for years Russian submarines were made of titanium. It is stronger than steel and non-magnetic. A boat made of titanium would be very strong and light also prohibitively expensive. Aluminium is much more common in marine construction.
Helicopters are made mostly of aluminium because it is strong, light and versatile
Copper is heavy and not as strong as aluminium.
Aluminium weighs less and it doesn't rust. It's about as hard as iron, too.
iron
Aluminium is a metal (an element), not an alloy. This means that it's only made up of aluminium atoms. It has no other impurities in it. Aluminium ore is called bauxite. This has aluminium plus other substances in it, but aluminium on its own is a metal with just aluminium atoms in it.
Many early telegraph cables were made of iron wire, but all modern ones are copper.
Various materials examples are: Concrete Aluminium Cast iron
An engine block is usually cast iron or aluminium.
Aluminium is used in a wide range of things. Airplanes are mostly made of Aluminium. It is used in variety of things because it is both strong and lightweight. It is often used for overhead power cables as it is very light and an excellent conductor and not scarce like copper.
Aluminium would be too brittle, light, and expensive
Most bike hubs are aluminium. Aluminium comes from Bauxite ore, which is refined and the metal aluminium extracted. Axles and bearings are generally steel, which comes from iron ore.
Pretty much anything apart from chain, axles, brake pads, tires and cables can be made of aluminium. Some common componentes in aluminium are: - rims -cranks -chain rings -seat post - handle bar -frame.
Pans can be made of various materials. they can can be made of: Aluminium, Stainless Steel or Cast Iron which is an older one.
Aluminium has some advantages over steel. Since it has a lower density than iron or steel, a car body made from aluminium will be lighter than the same car body made from steel. This results in improved fuel economy. Also, aluminium does not corrode easily, so a car body made from aluminium will corrode less, and may last longer, than one made from steel. However, aluminium is more expensive than steel. So a car made from aluminium is likely to be more expensive than one made from steel.