![]() ![]() ”Your physics are off, otherwise planes would only be able to maintain altitude by pitching upward.Īlso, the drag coefficient is only one part of the ballistic coefficient. if it takes one second for a bullet to hit the ground from 1 meter at 100m/s its gonna take 1 second for it to hit the ground at 2000m/s. things like drag simply slow the bullet down and cause that curve to compress. A bullet should always take the same time to hit the ground regardless of muzzle velocity unless another force is acting upon it due to gravity. I am trying to understand.↑ “ This is mostly right, except normal bullets dont gain much if any lift from increased muzzle velocity, that normally only happens with back spinning spheres. ![]() so it becomes a momentum issue the gas+the bullet vs the bullet alone.Īnd that's why I am talking to you guys because you are, presumably, far better educated than I and can rationalize the observed data vs the theoretical. because the bullet has a longer time exposed to the propellant gas pressure. that's why long barrel guns have higher velocity than short barrel ones. and I can't help but think the same thing happens with the bullet. there is no way a pitchers hand is moving at a 141 fps to thor a 100 mph fast ball all you have to do is watch it with a stop watch and the time it takes for a full forward movement vs the linear distance isn't even close to that. where once the bat contact the ball and that system has a given momentum so once the ball leaves the bat ( like a hub cap falling off a moving car ) the ball has the same system momentum and being of substantially less mass, now much achieve a higher speed and therefore accelerates.Īnd I am thinking that's what happens to the pitched ball as well. I suppose this could be a conservation of momentum deal. it has to go from 0 velocity in the outgoing direction to some max v over some distance and time. Ignoring the vector analysis of the trajectory and just discussing the velocity/acceleration question, there can be no way that the ball achieves max V in the other direction instantaneously as it leaves the bat. then the ball accelerates in the other direction to some terminal V before it slows down and begins to fall. at the instant of impact the ball has zero velocity. the bat of a given mass makes contact with the ball in the opposite direction and imparts some given force. So the ball approaches the bat at some given velocity. Ignore, for the sake of discussion, the compressibility of the ball and the coefficient of restitution of the bat. take the example of a baseball bat hitting a pitched baseball. somebody please remind me what the truth is, please. of distance vs time rather than a straight line. the pitchers arm isn't moving at 100 mph when the ball leaves his hand ( is it ? ) so the ball accelerates to max v and then slows down. Just like a pitcher throwing a 100 mph fast ball. max v occurs not at the muzzle but somewhere down range. but in the real world it just seems, just like the guy throwing the rock, that the bullet accelerates for some period of time AFTER it leaves the barrel before it reaches an equilibrium with the drag and starts slowing down. how far does it travel before it hits the ground ? " that was all linear. " someone throws a rock of x mass with a force of y lbs off a cliff z feet high in a vacuum. I did that calculation a hundred times in school. so the bullet is immediately subjected to a drag force as a function of air versus its instantaneous velocity and gravity pulling it down. then any unbalanced force acts to offset that acceleration. a given force imparted to a given mass results in a given acceleration. I understand the logic and science of their position but I can't get it to make sense to me. their assertion is that, once the gases stop pushing the bullet, that everything after that is " slowing down. the absolute velocity of the bullet at the instant that it clears the barrel. When you talk to gun guys, they say that the maximum velocity that a bullet reaches is the muzzle velocity. Hi, my high school physics is letting me down here and I just have to get an explanation. ![]()
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