I'm trying to figure out the role that kinetic energy and momentum play in projectile collisions. there are two cases: 1.) when the projectile becomes completely embedded in the target and 2.)When the projectile completely passes through the target and flys out the other end.(adsbygoogle = window.adsbygoogle || []).push({});

If the collision is completely inelastic in situation 1, then wouldn't the impact force just be impulse? given by the equation: Force*delta(t)=change in momentum. If this is true, then isn't the destructive force a projectile related solely to it's momentum andnotit's kinetic energy? The only situation i see where having a high kinetic and low mometum is better than having really high momentum and low energy, is situation 2.

I shoot bow and arrow, and my bow shoots a 25.7gram arrow 46.4m/sec, giving it a momentum of 1.19 kg*m/s. The energy is only 27.66J. Now compare this with a .22lr: 2.6 grams moving @ 330m/sec., which gives it only 0.858kg*m/s. But it has an energy of 141.5J.

Although my intuition tells me the bullet will do more damage, i don't understand why.

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# Kinetic Energy vs. Momentum in Projectile collisions

Can you offer guidance or do you also need help?

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