Which hits the ground first?
06-12-2009, 02:35 PM
#1
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Which hits the ground first?
You head out to the Salt Flats to do some shooting; 7mm Remington Magnum, 139grain VMax bullet @ 3400 feet/sec.
After setting up your rifle so that the centerline of the bore is exactly 36" above and parallel to the ground...which happens to be completely flat.
Now you set up the test rig which holds an unfired bullet exactly 36" above the ground and will drop said bullet when the fired bullet leaves the muzzle.
Which bullet hits the ground first?
After setting up your rifle so that the centerline of the bore is exactly 36" above and parallel to the ground...which happens to be completely flat.
Now you set up the test rig which holds an unfired bullet exactly 36" above the ground and will drop said bullet when the fired bullet leaves the muzzle.
Which bullet hits the ground first?
06-12-2009, 02:46 PM
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Define terms please-
is the "unfired bullet" just the projectile? or because it is "unfired", does it include the casing, charge and primer?
(either way, the answer is probably really close to "they both hit at the same time"- one would have a hard time proving or disproving any answer since the two events will take place so far away from each other)
is the "unfired bullet" just the projectile? or because it is "unfired", does it include the casing, charge and primer?
(either way, the answer is probably really close to "they both hit at the same time"- one would have a hard time proving or disproving any answer since the two events will take place so far away from each other)
06-12-2009, 02:50 PM
#7
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If the fired bullet travels only a short distance, then yes, both bullets hit the ground at the same time.
However, if the fired bullet travels far enough, the earth, being round, CURVES AWAY FROM IT. (Remember Newton's first law of motion: moving objects tend to travel in a straight line.)
Since the fired bullet has farther to fall, it takes longer to hit the earth, so the dropped bullet hits the ground first (by a teeny-tiny fraction of a second).
However, if the fired bullet travels far enough, the earth, being round, CURVES AWAY FROM IT. (Remember Newton's first law of motion: moving objects tend to travel in a straight line.)
Since the fired bullet has farther to fall, it takes longer to hit the earth, so the dropped bullet hits the ground first (by a teeny-tiny fraction of a second).
06-12-2009, 02:52 PM
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You head out to the Salt Flats to do some shooting; 7mm Remington Magnum, 139grain VMax bullet @ 3400 feet/sec.
After setting up your rifle so that the centerline of the bore is exactly 36" above and parallel to the ground...which happens to be completely flat.
Now you set up the test rig which holds an unfired bullet exactly 36" above the ground and will drop said bullet when the fired bullet leaves the muzzle.
Which bullet hits the ground first?
After setting up your rifle so that the centerline of the bore is exactly 36" above and parallel to the ground...which happens to be completely flat.
Now you set up the test rig which holds an unfired bullet exactly 36" above the ground and will drop said bullet when the fired bullet leaves the muzzle.
Which bullet hits the ground first?
If the fired bullet travels only a short distance, then yes, both bullets hit the ground at the same time.
However, if the fired bullet travels far enough, the earth, being round, CURVES AWAY FROM IT. (Remember Newton's first law of motion: moving objects tend to travel in a straight line.)
Since the fired bullet has farther to fall, it takes longer to hit the earth, so the dropped bullet hits the ground first (by a teeny-tiny fraction of a second).
However, if the fired bullet travels far enough, the earth, being round, CURVES AWAY FROM IT. (Remember Newton's first law of motion: moving objects tend to travel in a straight line.)
Since the fired bullet has farther to fall, it takes longer to hit the earth, so the dropped bullet hits the ground first (by a teeny-tiny fraction of a second).
06-12-2009, 02:52 PM
#11
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I would say the fired bullet because the force of the firing will cause it to accelerate faster than the bullet only utilizing gravity to move downward. In an unlimited freefall, if they were the same shape/mass then yes, eventually they would fall at the same rate (terminal velocity) but they initially propelled bullet would still be ahead of the dropped one.
However, I don't understand what the "centerline of the bore" is, but it sounds like maybe the bullet that is being fired is parallel to the ground? In which case, I have no clue because I don't know if a fired bullet falls at the same rate as one that is simply dropped. Also, the masses of the two objects are different if you really get into things.
However, I don't understand what the "centerline of the bore" is, but it sounds like maybe the bullet that is being fired is parallel to the ground? In which case, I have no clue because I don't know if a fired bullet falls at the same rate as one that is simply dropped. Also, the masses of the two objects are different if you really get into things.
06-12-2009, 02:58 PM
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