Calculating the Mach angle

The cone created by the shock wave as an aircraft exceeds the speed of sound is called the Mach cone. We can calculate p, the

Pressure waves created by the jet expand as the aircraft moves along.

If the aircraft moves from O to C in a time t and the wave travels from A to C in the same time, then OA = vt and OC = vAt, where v is the speed of sound and vA is the speed of the aircraft. The Mach cone is the common tangent to all the wave fronts, so OAC is a right-angled triangle.

vAt vA

The half angle of the Mach cone becomes smaller as the speed increases.

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