Learn more physics!
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.
(republished on 07/11/06)
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