Video: Destroying The "Jet Effect"

Gil, excellent work. Although the full video is difficult to watch, it clearly shows what is expected. 

I have this comment about the test with the skull on the ladder. The momentum is clearly forward as can be seen in the movement of the ladder. The slow motion film clearly shows the ladder moving forward. The energy transfer is always in the direction of the projectile. In cases where the bullet goes thru the object, less energy is transferred, but the motion is still forward. If the skull was attached to the ladder, everything would move forward together, as we would expect. 

When a test like this allows for the bodies to separate (as with the skull and the ladder) many different things can happen. If the skull is sitting on the ladder with no resistance to forward motion, then the ladder should not move at all. What happened in this test is the skull applied a load to the top of the ladder as it tried to move forward. The skull snapped backwards as a secondary motion due to deflection of the two bodies. This test is not an accurate representation of the actual situation in Z312-Z313. In my text, I compared this scenario with a lab test we did in a physics lab for the Engineering curriculum. I will present it under a separate post. 

Anthony Rante, P.E.