Comments by "EarthSurferUSA" (@EarthSurferUSA) on "How Long it takes for Arrows to fall back down?" video.

  1. It depends on the speed it leaves the gun. The crossbow shoots an arrow at about 450 feet per second. Most bullets start at about 800 or 900 feet per second, so my guess, it would be about double the time for a slower bullets.
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  2. I know the math is simple, decelerate and accelerate in a vacuum at "32 feet/second/second", and he gave us the starting speed, (energy would not matter in a vacuum), but I did not crunch the numbers, (which is much harder if you add the air in the equation). Good guess at 18 seconds for the crossbow. It's fun to impress your self with your excellent intuition. I think his reaction time was about .5 seconds off. :)
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  3. Thin roof. The table was not much better.
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  4. We don't know the weight of the arrow, (Bolt), or it would be easy to figure out. But using the numbers he gave us (191 fpe I think he said), his arrow should weigh 389.3 grains. If that is a close weight to the arrows, (and I bet it is), it should be right. I just looked up one site that says the standard weight for a crossbow bolt is 400-500 grains. His numbers seem on par to me.
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  5. My guess is that at least 2 of those arrows would go through the thin roof,--and maybe have gone through that table. He was the smart guy in the vid.
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  6. Yea. In a vacuum, the arrow would be hitting the table at the same speed it left the Bow's. I don't know how much the air would slow it down, but the air drag can be measured with a chronograph, and then the speed hitting the table can be figured out. My butt would have been under the truck too. :)
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