Comments by "Animal Farm" (@animalfarm7467) on "SmarterEveryDay" channel.

  1. An excellent video but one question: When you measure the angle of the shock-wave to the trajectory in your first video, you get approximately arctan(5/8) = 32 degrees. The sine of 32degrees is 0.53 and the inverse of 0.53 is 1.8867 which I agree is the Mach number. Assuming the local air temperature and density give the local speed of sound as 343m/s, the speed of the 50cal projectile accounting for error in angle measurement is around 650m/s. Most 50cal projectiles have muzzle velocities of between 850m/s and 930m/s. So what round did you use?
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