Solution: Mach Cone and Shock Waves
Diagram Analysis
The diagram shows Observers A, B, and C located on a straight line that forms a tangent to multiple circular wavefronts. The aircraft D is at the apex of this V-formation.
Fig: The Mach Cone created when Velocity(Source) > Velocity(Sound)
Conclusion
The circular waves cannot propagate fast enough to get ahead of the aircraft. They pile up to form the conical “Shock Front.” This occurs only when the aircraft speed is supersonic (higher than the speed of sound).
Option (c)