A Bullet's (lack of) Transfer Of Kinetic Energy

[Bill Brown]

A baseball bat moving toward a human head has kinetic energy. This is what is making the bat move toward the head, the kinetic energy.

When the bat strikes the head from the front, the kinetic energy transfers from the bat to the head, moving the head violently backwards (in the same direction the bat was moving).

The kinetic energy gets transferred from the bat to the head and it is this energy which causes the head to move violently backward.

 

Now.....

 

A bullet moving toward a human head has kinetic energy. This is what is making the bullet move toward the head, the kinetic energy.

When the bullet strikes the head from the front, not enough kinetic energy is transferred from the bullet to the head to cause the head to move violently backward.

Unlike the bat, the bullet keeps almost all of it's kinetic energy as it passes through the head (a very tiny amount of the kinetic energy will ripple out as a shockwave through the tissue).

Because most of the kinetic energy of a bullet that has struck the head from the front stays with the bullet and is not transferred to the head, the head will not move violently backward.

 
In other words, a bullet striking a head will not transfer enough of it's kinetic energy to cause the head to move violently. A baseball bat striking the head will indeed transfer almost all of it's kinetic energy and this will cause the head to move violently.

A bullet's (lack of) transfer of kinetic energy. Learn it. Love it.

[Marjan Rynkiewicz]

A baseball bat moving toward a human head has kinetic energy. This is what is making the bat move toward the head, the kinetic energy.
[NEWTON SAID THAT A BAT MOOVS ALONG AT A UNIFORM VELOCITY UNLESS FORCE ACTS ON THE BAT].
[THERE IS NO SUCH THING AS KINETIC ENERGY – KE EXISTS IN MATHLAND ONLY].
[THE BAT & HEAD HAVE RELATIVE MOTION & GRAVITATIONAL MASS & INERTIAL MASS].

When the bat strikes the head from the front, the kinetic energy transfers from the bat to the head, moving the head violently backwards (in the same direction the bat was moving). The kinetic energy gets transferred from the bat to the head and it is this energy which causes the head to move violently backward.
[KE DUZNT TRANSFER – NEWTON SAID THAT WE HAVE PAIRS OF OPPOSITE FORCES – EVERY ACTION HAS A REACTION].

Now..... A bullet moving toward a human head has kinetic energy. This is what is making the bullet move toward the head, the kinetic energy. When the bullet strikes the head from the front, not enough kinetic energy is transferred from the bullet to the head to cause the head to move violently backward. Unlike the bat, the bullet keeps almost all of it's kinetic energy as it passes through the head (a very tiny amount of the kinetic energy will ripple out as a shockwave through the tissue). Because most of the kinetic energy of a bullet that has struck the head from the front stays with the bullet and is not transferred to the head, the head will not move violently backward. In other words, a bullet striking a head will not transfer enough of it's kinetic energy to cause the head to move violently. A baseball bat striking the head will indeed transfer almost all of it's kinetic energy and this will cause the head to move violently. A bullet's (lack of) transfer of kinetic energy. Learn it. Love it.
[THE SLUG FROM HICKEY'S AR15 AT Z313 BROKE UP & LOST SPEED IN JFK'S HEAD – IT IZ OK TO SAY THAT ENERGY WAS "LOST" – ENERGY WENT INTO THE BREAKING UP & INTO IMPARTING MOTION TO BRAIN ETC & INTO HEAT & INTO NOISE & INTO PHOTONIC RADIATION ETC – ALLTHO AS I SAID IMPACT IS ABOUT FORCES NOT ENERGYS].
[THE REMNANT SLUG HAD ENUFF MOTION (AFTER VEERING SAY 6 DEG IN JFK'S HEAD) TO CRACK THE WINDSHIELD].
[JFK'S HEAD INITIALLY WENT FORWARD AN INCH -- & THEN WENT BACKWARDS DUE TO EXPLOSIVE FORCES & LATER POSSIBLY FURTHER BACKWARDS DUE TO MUSCULAR REACTIONS].

[MOMENTUM IS FUNNY  -- IT TOO EXISTS IN MATHLAND – MOMENTUM IS I THINK MORE FUNDAMENTAL THAN ENERGY – MOMENTUM IS A PRODUCT OF FORCE & TIME – KINETIC ENERGY IS A PRODUCT OF FORCE & DISTANCE].
[ANY FRICTION IN A SIMPLE IMPACT ROBS KE, BUT DUZNT ROB MOMENTUM – THIS IS DIFFICULT TO UNDERSTAND – JUST SAYING].

[Andrew Mason]

It is momentum, not kinetic energy, that causes the head to move with the bat much more than the bullet.

A one kg bat moving at a velocity of 30 m/s (65 mph) carries a kinetic energy of ½mv²=.5 x 1 x 30x30=450 Joules of kinetic energy.

A 10 g (.01 kg) MC bullet moving at 650 m/s carries just over 2000 Joules, more than 4 times as much energy as the bat.

However, the bat carries 1 x 30 = 30 kg m/s or 30 Ns of momentum whereas the bullet carries only  .01 x 650=6.5 kg m/s of momentum, or less then 1/4 of the bat's momentum. If the bullet does not lose all of its momentum in passing through the body, it transfers even less momentum than that.

This is why the jet effect works.  The transfer of energy to a much larger mass of brain matter that then explodes out of the head (due to the large amount of energy transferred as the flattened bullet builds up pressure within the skull) carries more momentum than the incoming bullet.  This imparts rearward momentum to the head that is seen after z313.

[Marjan Rynkiewicz]

It is momentum, not kinetic energy, that causes the head to move with the bat much more than the bullet.

A one kg bat moving at a velocity of 30 m/s (65 mph) carries a kinetic energy of ½mv²=.5 x 1 x 30x30=450 Joules of kinetic energy.

A 10 g (.01 kg) MC bullet moving at 650 m/s carries just over 2000 Joules, more than 4 times as much energy as the bat.

However, the bat carries 1 x 30 = 30 kg m/s or 30 Ns of momentum whereas the bullet carries only  .01 x 650=6.5 kg m/s of momentum, or less then 1/4 of the bat's momentum. If the bullet does not lose all of its momentum in passing through the body, it transfers even less momentum than that.

This is why the jet effect works.  The transfer of energy to a much larger mass of brain matter that then explodes out of the head (due to the large amount of energy transferred as the flattened bullet builds up pressure within the skull) carries more momentum than the incoming bullet.  This imparts rearward momentum to the head that is seen after z313.

I suspekt that the explosion involves latent energy of a state of change from liquid to gas.
This would logically rob energy from the explosion.
But, we also know that a slight disturbance of a say bottle of soda or the introduction of an object or a substance can result in a sudden explosive release of gas with more energy than the energy (or momentum) of the disturbance or introduction or substance.