HP-15C The time an object takes to fall to the ground

[Dieter]

(12-11-2016 11:49 AM)Gamo Wrote:  According to the User's Manual Page 14 example of the basic programing about
the time an object takes to fall to the ground.

I try to find the exact second from the distance from it.

Second Height (Meter)
1 4.9
2 19.6
3 44.1
4 78.4

The formula is heigth [m] = 4,9 x time[s]^2
Where 4,9 is 1/2 of the well known 9,8 m/s here on earth.

(12-11-2016 11:49 AM)Gamo Wrote:  Percent difference between 4.9 to 19.6 is 300% when add 78.4 + 300% = 313.6

19,6 simply is 4x 4,9. And 313,6 is 4x 78,4.

(12-11-2016 11:49 AM)Gamo Wrote:  313.6 meter using the programed formula equal to 8 second

Sure. If the time doubles, the height changes by a factor of 2² = 4. Or +300%, if you prefer.

Or: if the height quadruples (from 78,4 to 313,6 m) this means that the time changes by a factor of 2, e.g. here from 4 to 8 seconds.

(12-11-2016 11:49 AM)Gamo Wrote:  8 313.6
16 1254
32 5016
64 20064
128 80256

the number in seconds is 8, 16, 32, 64, 128 look like a computer bits numbers.
Just curious and share the though.....

I'm not sure what to want to say with the last table, but it's nothing but simple math. ;-)
If you add 300% to the height, i.e. multiply the height by 4, the corresponding time doubles (=sqrt(4)), as do the listed seconds (8, 16, 32, ...).

Dieter