Printing:
What is the deepest point in the ocean? Overcoming a crushing 1094 atm
Lets look at the stress in the walls of spherical shell with thickness, t, due to the force from the pressure.
Stress: ! =#$%&''(%&
)
! =*+,-
.
)
! =*+,-
.
/+,-0
! =*,-
/0
We see that when the 12,3445,3 is large, our stress is big, and we see when our wall thickness is small, our stress is also big, and we are getting close to the breaking point.
ConclusionsThe pilot sphere in 1960 used a sphere with a radius of 7.5ft and 5in thick steel walls. The pilot sphere in 2012 used a sphere with a radius of 3.75ft and 2.5in thick steel walls. This is consistent with our equation for stress we derived.
! =678
2:
This equation tells us to reduce the stress on our walls and stay below the breaking point, we should use a sphere with a smaller radius, and use thicker walls.
Overcoming Hydrostatic Pressure: Exploring the Ocean’s DepthsTony Connors | Department of Physics | Colorado College
Pressure gradient of the oceanWearealwaysunderpressure,duetotheatmospherepushingdownonusfromabove.Thesameishappeningwhenwedivedowninapoolofwater.Thedeeperdownyoudive,themorewaterisaboveyou,pushingdownonyouinadditiontothepressureoftheatmosphere.Theamountofpressureincreasesthedeeperyoudive.Thefollowingequationdescribesthisphenomenon.
6 ℎ = WXℎ + 6)08
Pressure at surface 6)08 = 1[:\ = 1013256[, Deepest point h = 10994 m,
Density of ocean water W = 1027cd
8e,
Acceleration due to gravity X = 9.818
4.
Pressure 6.8 miles (35,904 ft) under the ocean surface
6 ℎ = WXℎ + 6)08
6 10994\ = 1027cd
8e9.81
8
4.10994 m + 1013256[
6 10994\ = (1.10763 ∗ 10jcd
8∗4.) + (1.01325 ∗ 10l6[)
6 10994\ = 1.10864 ∗ 10j6[
6 10994\ = (1.10864 ∗ 10j6[) ∗m)08
m.nmo/l∗mnp*)
q rsttuv = rstu. rwxyz
Missions to Challenger Deep
Jacques Piccard and Dan Walsh, January 23, 1960, 10,911 meters (35,797 feet)
James Cameron, March 26, 2012, 10,908 meters (35,787 feet)
t
{8a
t
2|78
12,3445,3
Acknowledgements
Thank you to Professor Phillip Cervantes, Professor Stephanie DiCenzo and Professor Tamara Barriquand for helping me with this research.
Thank you to our paraprof, Zoe Pierrat for helping me with my poster.
Breaking Point
Inelastic Region
Yield point
https://en.wikipedia.org/wiki/Stress%E2%80%93strain_curve
Elastic Region.Obeys Hooke’s Law
A stress-strain curve will tell us how much stress will cause our material to break. We want to be below the breaking point and within the elastic region.
Picture above: Trieste, 1960Picture to right: Deepsea Challenger, 2012
https://www.behance.net/gallery/2650097/Mariana-Trench-compared
https://en.wikipedia.org/wiki/Deepsea_Challenger#/media/File:Deepsea_challenger_deep-diving_submersible_DVC1.svg
https://en.wikipedia.org/wiki/Bathyscaphe_Trieste#/media/File:Trieste_nh96807.svg
Picture taken by Tony Connors