What height

[carsonking]

What height would a 14 stone medium build human have to jump from to reach terminal velocity?

[factor-fiction]

terminal velocity of human is around 53 m/s

using v^2=2gs, with v=53m/s and g=9.8 m/s^2:
2500/20=s
s=143m

Air resistance will affect the result but I suggest the amswer is pretty close

[factor-fiction]

I accidentally left in a line containing an approximated calculation before I launched Excel.

The terminal velocity of a falling human is around 53 m/s

using v^2=2gs, with v=53m/s and g=9.8 m/s^2:

s=143m

Air resistance will affect the result but I suggest the answer is pretty close

[wildwood]

There is no clear answer to your question. As you mention "jump", it is presumed this is done on purpose and the mode is important.
A spreadeagled jumper can slow her/is descend down to 120mph.
An 'diver' can easily reach three times that and the record is in excess of 600mph.

[Mr Chipps]

Don't do it. It's not worth it. Life's not that bad.

[mibn2cweus]

As anyone who has reached terminal velocity can attest (assuming they survive, of course) air resistance begins to slow acceleration, at a rate depending on their posture, long before attaining a terminal velocity of 53m/s increasing the distance required to do so considerably.