Pressure on a window of a submarine

AI Thread Summary
The discussion focuses on calculating the maximum safe depth for a submarine window based on its pressure tolerance. The window can withstand forces up to 1x10^6 N, leading to a calculated pressure of 3.2x10^7 Pa. The relevant pressure equation, p = p_o + ρgd, incorporates atmospheric pressure (1.01x10^5 Pa) and the density of water (1000 kg/m^3). The confusion arises around the relationship between different pressure variables, particularly how p' (total pressure) relates to p1 (pressure at the window) and atmospheric pressure. Understanding these concepts is crucial for solving the problem accurately.
indietro
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Homework Statement


a research submarine has a 20 cm diameter window 8 cm think. the manufacturer says the window van withstand forces up to 1x106N. What is the submarine's maximum safe depth?


Homework Equations


p = po + \rhogd


The Attempt at a Solution


p = F/A = 1X106 / 0.03 = 3.2x107 Pa

so now do i use p = po + \rhogd ??

but if i do what would be my \rho?
\rho = m/v = m/\pir2h
how would i find mass?

thanks in advance for help!
 
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ok so i solved it with the help of a different post but i had a question:
she does p' = p1 + \rhogd
p' - p1 = \rhogd

and then she says that p1 = 1x105 Pa > atmospheric pressure. I was just wondering why?

can someone explain how
\Deltap = p1 - po relates or is used in conjunction with p' = p1 + \rhogd? is \Deltap = p'
 
anyone??
 
i really just can't seem to wrap my head around pressure concepts, if someone knows how to explain it clearly or knows a website where i can see examples and stuff that would be great!
 
indietro said:
ok so i solved it with the help of a different post but i had a question:
she does p' = p1 + \rhogd
p' - p1 = \rhogd

and then she says that p1 = 1x105 Pa > atmospheric pressure. I was just wondering why?
it gets confusing with so many different letter variables like p, p_1, p_o, p', \rho (and Pa for Paschals to boot), so let's define the variables:

let

p_o = atmospheric pressure = 1.01(10^5) Paschals
p = total pressure at depth d
\rho = density of water = 1000kg/m^3)

Now when the top of the water is not sealed off (that is, it is exposed to the atmosphere),
p = p_o + \rho gd, that is , the total pressure at depth d is the sum total of the atmospheric pressure and the water pressure at that depth.
 
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