Depends on how deep the person is, but since they’re scuba diving in somewhat shallow waters (no wet suit, at the bottom but can see, etc.) not a terribly high amount.
If we assume 50 metre depth and 1 metre diametre plug:
p=ρ×g×h+p0 = 1022 kg/m3(9.8m/s2)(50m)+101kPa = 602 kPa or 87 psi for you Americans.
Area plug = πr2 = π(0.5m)2 = 0.785 m2
F = PA = 602 kPa x 0.785m2 = 472.6 kN or 106 238 lbf
So, far above what a person could pull, but not absurd amounts considering the sizes involved.
Edit: fucked up my units and force formula, whoopsie.
I wonder how much force that would take to pull.
Depends on how deep the person is, but since they’re scuba diving in somewhat shallow waters (no wet suit, at the bottom but can see, etc.) not a terribly high amount.
If we assume 50 metre depth and 1 metre diametre plug:
p=ρ×g×h+p0 = 1022 kg/m3(9.8m/s2)(50m)+101kPa = 602 kPa or 87 psi for you Americans.
Area plug = πr2 = π(0.5m)2 = 0.785 m2
F = PA = 602 kPa x 0.785m2 = 472.6 kN or 106 238 lbf
So, far above what a person could pull, but not absurd amounts considering the sizes involved.
Edit: fucked up my units and force formula, whoopsie.
If I’m ever in this situation, I’ll bring some friends.
You mean kN / lbf for the final answer.
You’re absolutely correct, good eye.
It also depends on what’s on the other side. It might not be vacuum, though whatever it wouldn’t likely be in the hundreds of kilonewtons
Crab pipe. 'Nuff said