Coba jelasin Di dalam aliran supersonik dari Gelombang kejutan dalam bahasa melayu dong

The abruptness of change in the features of the medium, that characterize shock waves, can be viewed as a phase transition: the pressure-time diagram of a supersonic object propagating, shows how the transition induced by a shock waves is analog to a dynamic phase transition.

When an object (or disturbance) moves faster than the information about it can be propagated into the surrounding fluid, fluid near the disturbance cannot react or "get out of the way" before the disturbance arrives. In a shock wave the properties of the fluid (density,pressure, temperature, velocity, Mach number)  change almost instantaneously. Measurements of the thickness of shock waves have resulted in values .2 micrometers (10-5 in), which is on the same order of magnitude as the mean free gas molecule path.  In reference to the continuum, this implies the shock wave can be treated as either a line or a plane, if the flow field is 2d or 3d respectively.

Gelombang kejutan terhasil apabila kelajuan suatu bendalir melebihi kelajuan bunyi. Gelombang bunyi bergerak menentang arus mencecah suatu titik di mana ia tidak boleh bergerak jauh lagi, menambahkan tekanan yang tertumpu di kawasan tersebut lalu menghasilkan gelombamg tekanan bertekanan tinggi secara mendadak.

Shock waves are not conventional sound waves; a shock wave takes the form of a very sharp change in the gas properties on the order of a few mean free paths (roughly micro-meters at atmospheric conditions) in thickness.  Shock waves in air are heard as a loud "crack" or "snap" noise. Over longer distances a shock wave can change from a nonlinear wave into a linear wave, degenerating into a conventional sound wave as it heats the air and loses energy. The sound wave is heard as the familiar "thud" or "thump" of a sonic boom, commonly created by thesupersonic flight of aircraft.

The shock wave is one of several different ways in which a gas in a supersonic flow can be compressed. Some other methods are isentropiccompressions, including Prandtl-Meyer compressions. The method of compression of a gas results in different temperatures and densities for a given pressure ratio, which can be analytically calculated for a non-reacting gas. A shock wave compression results in a loss of total pressure, meaning that it is a less efficient method of compressing gases for some purposes, for instance in the intake of a scramjet. The appearance of pressure-drag on supersonic aircraft is mostly due to the effect of shock compression on the flow.