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Hi all. My understanding of physics is...well not so good.

I have a question or three that I'll try to relate with my limited knowledge, so bare with me.

With bullets, a rating of KE is generally given by the bullets known mass(given in grains/1/7000th pounds) and velocity(given in fps). The momentum, however is not given. Momentum is mass*velocity correct? I've been told that the KE is the abilty to do work. Bullet energy(from manufacturers) is usually measured in FT/LBS. How does KE relate to momentum? From what I see there is virtually no relation. For instance, a projectile may have much more momentum while having much less KE and vice versa. It seems to me that having much greater momentum per it's Kinetic energy would give more "abilty to do work". An example, a 100 grain bullet at a velocity of 1500fps has nearly identical KE to a 250 grain bullet moving at a velocity of 950fps, yet the 250 grain bullet will have over 50% more momentum. How does the extra momentum not translate into more work, since it will have more resistance to change in velocity and direction on impact? Maybe...the high vs. low momentum bullets are using available energy in different ways? Given that the total kinetic energies of the two projectiles are equal I know that thier total abilities are equal, and I am not questioning that, just trying to gain an understanding.

BTW, are there any units of measurement for momentum that can be found with a known mass and velocity?

Thanks in advance for any replies. I've not had the chance to study physics and am admittedly ignorant on this subject, but have a desire to learn. Please go easy on me if I'm way off base here.

I have a question or three that I'll try to relate with my limited knowledge, so bare with me.

With bullets, a rating of KE is generally given by the bullets known mass(given in grains/1/7000th pounds) and velocity(given in fps). The momentum, however is not given. Momentum is mass*velocity correct? I've been told that the KE is the abilty to do work. Bullet energy(from manufacturers) is usually measured in FT/LBS. How does KE relate to momentum? From what I see there is virtually no relation. For instance, a projectile may have much more momentum while having much less KE and vice versa. It seems to me that having much greater momentum per it's Kinetic energy would give more "abilty to do work". An example, a 100 grain bullet at a velocity of 1500fps has nearly identical KE to a 250 grain bullet moving at a velocity of 950fps, yet the 250 grain bullet will have over 50% more momentum. How does the extra momentum not translate into more work, since it will have more resistance to change in velocity and direction on impact? Maybe...the high vs. low momentum bullets are using available energy in different ways? Given that the total kinetic energies of the two projectiles are equal I know that thier total abilities are equal, and I am not questioning that, just trying to gain an understanding.

BTW, are there any units of measurement for momentum that can be found with a known mass and velocity?

Thanks in advance for any replies. I've not had the chance to study physics and am admittedly ignorant on this subject, but have a desire to learn. Please go easy on me if I'm way off base here.

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