how would i calculate the velocity of a punch from visual mach cone/pressure waves?

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math_noob_1

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Hello free math help forum!

I was wondering what methodologies I would need to employ to calculate the velocity (for then subsequent kinetic energy) of several superman punches that result in what appears to be the breaking of sound barrier?

Please find the examples below:

streamable.com

Watch final_6216549bd7101f00bda3a95a_197408 | Streamable

Watch "final_6216549bd7101f00bda3a95a_197408" on Streamable.
streamable.com

Thanks!
 
I did a quick search on the internet. Several sources say that pressure waves don't have a set speed. They can propagate faster than the speed of sound. Therefore I think you're barking up the wrong tree. You might be better off working out the energy required to shoot a heavyish body through several warehouse walls. I'm not volunteering for that experiment, my days of being a human cannonball are well and truly over ⛑️:LOL:
 
Cubist said:
I did a quick search on the internet. Several sources say that pressure waves don't have a set speed. They can propagate faster than the speed of sound. Therefore I think you're barking up the wrong tree. You might be better off working out the energy required to shoot a heavyish body through several warehouse walls. I'm not volunteering for that experiment, my days of being a human cannonball are well and truly over ⛑️:LOL:
Click to expand...
thank you for the reply, cubist!

i had considered using that approach initially (energy required to fragment/destroy materials) but the scene was fairly blurry and it's hard to discern what is what in that regard. as example if i know the velocity of the punch and the mass of average human hand - i can calculate how much energy is in that one action. then i could use work equation (s = w/f) from the actors mass to determine how far that energy would displace said mass. then you can compare real life vs what transpired on scene.

i saw someone on another forum use methodologies i don't quite understand to calculate the velocity of a punch from the angle of the mach cone in comparison to the scenes horizontal plane.

here is a link to the post
 
math_noob_1 said:
here is a link to the post
Click to expand...
That post seemed to assume that a pressure wave travels at the speed of sound. This isn't necessarily true since apparently they don't have a set speed.

Another potential show-stopper is that I couldn't see a cone formed by a pressure wave in the video clip that you posted. Are you sure that there is one? I just saw many circular waves that expanded over several frames. Maybe I missed it, can you point to a particular time in the video clip? I think it would have to be viewed from the side, and might appear like the following state-of-the-art rendering ? ...

Code: 
     cone shaped
        \  wave
          \
            \      
____________  \
____________|FIST  -> direction of punch
              /
            /
          /
        /
 
Cubist said:
That post seemed to assume that a pressure wave travels at the speed of sound. This isn't necessarily true since apparently they don't have a set speed.

Another potential show-stopper is that I couldn't see a cone formed by a pressure wave in the video clip that you posted. Are you sure that there is one? I just saw many circular waves that expanded over several frames. Maybe I missed it, can you point to a particular time in the video clip? I think it would have to be viewed from the side, and might appear like the following state-of-the-art rendering ? ...

Code: 
     cone shaped
        \  wave
          \
            \  
____________  \
____________|FIST  -> direction of punch
              /
            /
          /
        /
Click to expand...
thank you for another reply, cubist!

the vfx guys in MoS stated that the visuals on punches were mach cones. the tv show clip above is heavily influenced by the movie franchise. so i can only infer that's the case here too.

here's the gif example the person from the post i linked to you used to calculate from. i still don't understand the methodology he employed.

gifit_1645810284438.gif

a specific example from the video i shared with you

gifit_1645810483770.gif

btw very impressive ascii art example haha.
 
Sorry I don't think I can help because I can't see a cone. I also have no idea where the "3.5 degree angle", mentioned in the linked post, was measured ?‍♂️ Curious!
 
Cubist said:
Sorry I don't think I can help because I can't see a cone. I also have no idea where the "3.5 degree angle", mentioned in the linked post, was measured ?‍♂️ Curious!
Click to expand...
oh, okay. no problem. thank you for your time anyway!
 
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