Question

Explain why:
(a) Air is used to inflate tyres.
(b) Steel is used to make railway lines.

Answer 1

Hint:There are three states of matter, solid, liquid and gases. All the three states of matter show different characteristics. Solids have definite composition, shape and volume, liquids have definite volume but do not have definite shape and gases have no definite volume and shape.

Complete step by step answer:(a) Air does not have any fixed shape or any fixed volume, the air takes the shape of any substance in which it is put in. Air is used to inflate the tyres because as the air is blown inside the tyre, it takes the shape of the tyre due to the large intermolecular spaces available in the air. When air is blown inside the tyre, the particles of the air distribute equally through the diffusion process inside the tyre giving the volume a proper balance.
(b) Steel is solid metal where particles in the steel are present in the fixed composition. The steel is used in making railways because it is flexible metal, It has the property to expand. In summers the steel expands but it does change its shape thus steel is used to make railways line because it only gets bigger in size and make sure that the tracks are safe to travel by the trains.

Note: The liquids can be used to fill up the tyre but due to its heavy volume and pressure it will exert more pressure in the tyre as compared to the atmospheric pressure which will result in the explosion of tyre.