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There are quite a few JJK calcs using this Mach cone angle method to find the speed of Piercing Blood. Now other than issues regarding the POV in most Piercing Blood panels not giving us a side profile view of the projectile, my primary concern is that what these calcs are measuring is not a Mach Cone, it is the vapor cone.
I've noticed that some people tend to conflate a vapor cone with a sonic boom even though they are two distinct phenomena. When an object is moving at Transonic speeds (within the Mach 0.8 to Mach 1.2 range), the air around it will accelerate to flow around the object which causes it to decrease in pressure and temperature, if the temperature in this low pressure region drops below the dew point then the water in the air condenses and becomes visible like a cloud. The conditions for the formation of a visible vapor cone are less favorable the further an object is into supersonic speed which makes sense because aerodynamic heating counteracts the cooling needed for the condensation, that's why you won't see a fighter jet forming a vapor cone when it's flying at like Mach 2.
The Mach cone is the envelope of shock waves created by an object exceeding 343 m/s in air. If an object is symmetric with uniform flow and steady motion then the Mach cone will be axisymmetric in the direction of travel, like this and not like this. Furthermore, a Mach cone is generated at the tip of the object because it is the continuous source of the pressure disturbances the object creates as it moves through the air faster than sound, this forms the vertex of the conical shock wave envelope.
As a bonus, here's Human Naoya producing a vapor cone when he's moving at Transonic speed and then Curse Naoya having to accelerate for 5 pages straight before forming a vapor cone.
Agree: SunDaGamer, Damage3245, TheRustyOne
Disagree:
I've noticed that some people tend to conflate a vapor cone with a sonic boom even though they are two distinct phenomena. When an object is moving at Transonic speeds (within the Mach 0.8 to Mach 1.2 range), the air around it will accelerate to flow around the object which causes it to decrease in pressure and temperature, if the temperature in this low pressure region drops below the dew point then the water in the air condenses and becomes visible like a cloud. The conditions for the formation of a visible vapor cone are less favorable the further an object is into supersonic speed which makes sense because aerodynamic heating counteracts the cooling needed for the condensation, that's why you won't see a fighter jet forming a vapor cone when it's flying at like Mach 2.
The Mach cone is the envelope of shock waves created by an object exceeding 343 m/s in air. If an object is symmetric with uniform flow and steady motion then the Mach cone will be axisymmetric in the direction of travel, like this and not like this. Furthermore, a Mach cone is generated at the tip of the object because it is the continuous source of the pressure disturbances the object creates as it moves through the air faster than sound, this forms the vertex of the conical shock wave envelope.
As a bonus, here's Human Naoya producing a vapor cone when he's moving at Transonic speed and then Curse Naoya having to accelerate for 5 pages straight before forming a vapor cone.
Agree: SunDaGamer, Damage3245, TheRustyOne
Disagree:
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jjk can't catch a break. this makes sense though
