# B Deepest Hole In The World

1. May 7, 2016

### Newtonfalls

Hi,

just saw an documentary about "the deepest hole in the world" on NG:
<link to video deleted>
Can anyone tell what it is, and what is the exact quotation to determine the height
(with fricton stone-pipe)

Last edited by a moderator: Sep 4, 2016
2. May 7, 2016

### davenn

hi there,
welcome to PF

Sorry but I have a lot of problems believing that video. I suspect some of the sound effects have been added

here is a wiki link to that is the deepest borehole drilled

https://en.wikipedia.org/wiki/Kola_Superdeep_Borehole

so, if nothing else, the title of that video is false for a start

cheers
Dave

Last edited by a moderator: Sep 4, 2016
3. May 7, 2016

### Staff: Mentor

Edit: Seems to be a new record on how fast Murdoch ruined a once excellent tv channel.

Last edited by a moderator: Sep 4, 2016
4. May 12, 2016

### olgerm

If you not to consider resistance forces (like air resistance), then
$h=v \cdot(t + \frac{v}{g}- v \cdot \sqrt{\frac{1}{g}\cdot(\frac{1}{g}+\frac{2\cdot t}{v})})≈4100*m≈4*km$
where:
• h is depth of hole h≈4102.3*m
• t is time from droping stone until hearing the the stone hit somebody t≈41*s
• g is gravitational acceleration g≈9.8*m/s2
• v is speed of sound v≈340*m/s
It is quite bad approximation, because the stone surely did not go break sound barrier. Real depth is smaller.
video sound may be fake.

5. Sep 4, 2016

### Staff: Mentor

Fake video. Thread closed.