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Because the masses involved are the same, recoil would be exactly the same as on Earth.Kerbouchard wrote:IIRC, a gun will fire on the moon. The recoil will probably send you flying, though.
but you wont be firmly plantedKBCraig wrote:Because the masses involved are the same, recoil would be exactly the same as on Earth.Kerbouchard wrote:IIRC, a gun will fire on the moon. The recoil will probably send you flying, though.
Sure you will. Physics work the same. It's not like being under water where you have a viscous material preventing your mobility. As long as your center of gravity is distributed between your feet the same as it is here you are just as "firmly planted".lunchbox wrote:but you wont be firmly plantedKBCraig wrote:Because the masses involved are the same, recoil would be exactly the same as on Earth.Kerbouchard wrote:IIRC, a gun will fire on the moon. The recoil will probably send you flying, though.
That seems correct assuming the muzzle velocity is the same, which it would probably be pretty close assuming the cartridge holding air thing worked (which we will assume because that makes this more interesting.)mr.72 wrote: Sure you will. Physics work the same. It's not like being under water where you have a viscous material preventing your mobility. As long as your center of gravity is distributed between your feet the same as it is here you are just as "firmly planted".
Escape velocity on the surface of the moon is almost 8,000 ft/sec, and I am not aware of any handgun that comes close to that. Acceleration due to gravity on the moon is about 1.6 m/s so if you shot the gun from a height of 1.6 meters perpendicular to the ground it would take one second for it to impact the ground in a level area. Since it is essentially a vacuum, there would be negligible loses due to air resistance and it would then travel very close to the muzzle velocity times 1 sec: for .45 ACP that would be close to 1,000 feet.Noting the reduced gravity and no frictional losses due to moving through air, the bullet would go a LONG way. Depending on the direction in which you fired it, it may not ever stop until it hit another object (in which case it may ricochet and continue going indefinitely), it may end up orbiting the moon, it may end up eventually in the ground on the moon if the angle is low enough for gravity to defeat the inertia of the bullet, it may go off into space and never stop, or it may end up caught in the earth's gravity and burning up in the earth's atmosphere.
Kind of an interesting thought.
Man, this forum has a bunch of geeks on it. I LOVE it!!!txmatt wrote:That seems correct assuming the muzzle velocity is the same, which it would probably be pretty close assuming the cartridge holding air thing worked (which we will assume because that makes this more interesting.)mr.72 wrote: Sure you will. Physics work the same. It's not like being under water where you have a viscous material preventing your mobility. As long as your center of gravity is distributed between your feet the same as it is here you are just as "firmly planted".
Escape velocity on the surface of the moon is almost 8,000 ft/sec, and I am not aware of any handgun that comes close to that. Acceleration due to gravity on the moon is about 1.6 m/s so if you shot the gun from a height of 1.6 meters perpendicular to the ground it would take one second for it to impact the ground in a level area. Since it is essentially a vacuum, there would be negligible loses due to air resistance and it would then travel very close to the muzzle velocity times 1 sec: for .45 ACP that would be close to 1,000 feet.Noting the reduced gravity and no frictional losses due to moving through air, the bullet would go a LONG way. Depending on the direction in which you fired it, it may not ever stop until it hit another object (in which case it may ricochet and continue going indefinitely), it may end up orbiting the moon, it may end up eventually in the ground on the moon if the angle is low enough for gravity to defeat the inertia of the bullet, it may go off into space and never stop, or it may end up caught in the earth's gravity and burning up in the earth's atmosphere.
Kind of an interesting thought.
As to ricocheting, the vacuum would not change the fact that the bullet and the ground would deform on impact absorbing most of the kinetic energy of the bullet.
As KBCraig pointed out it is the mass, not the weight that is the determining factor of recoil. The shooter's mass and the mass of the gun and bullet are the same on the moon as on earth.I am sure the recoil would feel different because you are "lighter" in terms of weight but the recoil would not likely knock you over unless you were shoulder-firing a 10 gauge shotgun or something like that.
Well that settles it.txmatt wrote: Escape velocity on the surface of the moon is almost 8,000 ft/sec,
I don't think air resistance would have anything to do with the recoil spring.G.A. Heath wrote:A semi-auto would need a stronger recoil spring in order to work properly as there is no air resistance. Speaking of the "lack of air resistance" you will see some, albeit minor, increased recoil due to that aspect.