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Q & A: The new style of falling objects

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Most recent answer: 10/22/2007
Is it true that if a bullet is fired from a gun, and a bullet is dropped manually at the exact same moment the fired bullet leaves the barrel, (assuming the bullet fired does not hit an object) both bullets will hit the ground at the same time?
- Greg St. John (age 27)
That's right. As odd as it sounds, the 2 bullets would land at exactly the same side (if we ignore air resistance).

The way to think about this is to think of the fired bullet as moving in 2 directions at the same time. The bullet is moving forward and down at the same time. The only reason it's moving down is because of gravity. Everything falls at the same speed, so both will land at the same time. You may think, "But it's moving so fast forward. Doesn't that change anything?" Actually, it doesn't. When you break something like the motion or something down into different directions (as long as they are at 90 degrees), the 2 different directions are totally independant of each other. So no matter how fast the bullet is going, it will still hit the ground at the same time as the other one.


(published on 10/22/2007)

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