How to Win a Bet with Physics

How to Win a Bet with Physics

In a survival show an engineer used a rock and a watch to predict depth of a cavern in order to win a bet. He did win the bet with his estimate being right on target. I believe he used physics to do this. He said the depth of the cavern was 80ft. Is this a feasible way to calculate height? If so could this feat be accomplished with physics?

h= v0t x .5at^2

v0=0

t=2.25

a=9.8

h= .5(9.8)(2.25)^2

h=(4.9)(5.06)

h=24.8m

h=81.4 ft

It seems he did use physics!! They used a rope and measured the cavern at about 82ft this means this is a feasible way to calculate depth.

I replicated this in my dorm down the staircase to check the accuracy of this method for myself, and I found:

h= .5(9.8)(1.45)^2

h= 10.3m or 32.8 ft

measured value equals 35ft. This method is accurate enough because 2 ft is a jumpable distance when climbing.