Arrow physics

[Zradix]

if two arrows are identical  except one weighs 688 grns and the other weighs  547 grns and both are traveling 150 ft per sec 20yds from the target. which arrow will be going faster just before it hits the target?

[Gary Sorensen]

The heavier arrow will initially have more kenetic energy due to its mass.  If both arrows are identical size and shape and traveling the same speed then they will lose the same amount of energy due to friction with the air. Therefore the heavier arrow will lose a smaller percentage of its energy and be traveling faster when it hits the target.

[JDL]

I'm a physicist. If they have the same cross section, the heavier one.

Picture throwing a balloon and then picture throwing a bowling ball of the same size...

This is an odd question b/c unless you are drawing farther on one arrow than another you shouldn't be getting the same speed. At least not from the same bow...

[Richie Nell]

The heavier arrow will always hold its momentum longer downrange.  When a heavy object is in motion it takes more to stop or change its motion than a lighter object.
Even the air friction will affect the lighter arrow thus slowing it down more than the heavy arrow.

[AALLFAB]

The balloon and bowling ball is a great example. I agree the heavier one will be going faster in the real world. Also agree you would have to shoot it out of a different bow to make it go the same speed. Jim

[Divinecedar]

It is very important to emphasize the fact that this is true if and only if they have the same cross section, so the actual diameter of the arrow and point selection would come into play.

[Richie Nell]

"if two arrows are identical"

Everything is constant except the weight.  It is the only variable.

[LKH]

da heby vun vins.

[Richie Nell]

yea thats what I was gonna say

[Bush]

It depends on how far the target is.

[Bjorn]

I'm not a physicist, but I did stay at a Holiday Inn; the heavier one.

[Richie Nell]

20 yards...IF they were shot 20 yards from the target.  If they were shot 40 yards from the target but going 150 fps at the 20 yard mark then they might not reach the target.  

Sorry. Just funnin.

[Zradix]

I thought so. Like to have a peer review! Thanks!