Free Republic
Browse · Search
News/Activism
Topics · Post Article

To: archy

Thanks for the post and good luck with your target practice.

And you have I’ve given me one more opportunity to apologize for my massive screwup:

A 58 foot drop in 3 seconds was incorrect. The formula is correct but the calculation went awry.

The real 3 second drop: 144 feet.


74 posted on 05/26/2017 2:23:00 PM PDT by InterceptPoint (Ted, you finally endorsed. About time.)
[ Post Reply | Private Reply | To 66 | View Replies ]


To: InterceptPoint
And you have I’ve given me one more opportunity to apologize for my massive screwup:

A 58 foot drop in 3 seconds was incorrect. The formula is correct but the calculation went awry.

The real 3 second drop: 144 feet.

Rule of thumb for those in the field without a ballistic computer/calculator/slide rule: NOT 3 x 32 fps, squared- that 32 fps drop is not a constant, and only applies to the terminal velocity after the first second- the initial rate of fall having been zero.

[The speed rises as the square root of height, but in direct proportion to time.]

The speed after 3 seconds is 96 feet per second. The total distance is 144 feet. Speed is acceleration times time. Distance is average speed times time. With constant acceleration, the average speed is the final speed divided by two.

So for the three-second bullet flight, the drop of the projectile [unless it's a spheroid musket or cannon ball, in which case see Robins or Bouriee] will approximate the height of a 14-story building- which sounds about right, compared to this shorter range and shorter church-steeple height elevation.

78 posted on 05/30/2017 10:55:05 AM PDT by archy (Whatever doesn't kill you makes you stronger. Except bears, they'll kill you a little, then eat you.)
[ Post Reply | Private Reply | To 74 | View Replies ]

Free Republic
Browse · Search
News/Activism
Topics · Post Article


FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson