# Thermodynamics Pressure Problem Help

• MechE2015
In summary, at the surface of the ice cap, there is 1 atm pressure and the corresponding temperature is 275 K.
MechE2015

## Homework Statement

The ice cap on the North Pole could be 1000 m thick with a density of 920 kg/m3. Find the pressure at the bottom and the corresponding melting temperature.

Steam tables
ΔP = ρgH

## The Attempt at a Solution

ΔP = (920 kg/m3)*(9.28 m/s2)*(1000) = 9022 kPa
P = Pinitial + 9022 kPa

I have no idea how to find initial pressure, which I think is my main information missing, then from there I would need to find the corresponding temperature.

MechE2015 said:

## Homework Statement

The ice cap on the North Pole could be 1000 m thick with a density of 920 kg/m3. Find the pressure at the bottom and the corresponding melting temperature.

Steam tables
ΔP = ρgH

## The Attempt at a Solution

ΔP = (920 kg/m3)*(9.28 m/s2)*(1000) = 9022 kPa
P = Pinitial + 9022 kPa

I have no idea how to find initial pressure, which I think is my main information missing, then from there I would need to find the corresponding temperature.
Welcome to Physics Forums.

The initial pressure is the pressure at the top of the ice cap ... which is the pressure pretty much anywhere on the surface of Earth.

You're a tad slow today, SteamKing!

What's on top of the polar ice cap? That's how you find the initial pressure.

Hint: it blows past you in the breeze.

Alright, so the pressure at the surface is 1 atm = 101.325 kPa, which gives me:

P = Po + ΔP = 101.325 + 9022 = 9123 kPa

From here, finding temperature would be found by maybe a P-T chart, where the substance goes from solid -> liquid? Around 275 K is what I get.

MechE2015 said:
Alright, so the pressure at the surface is 1 atm = 101.325 kPa, which gives me:

P = Po + ΔP = 101.325 + 9022 = 9123 kPa
Looks good.
From here, finding temperature would be found by maybe a P-T chart, where the substance goes from solid -> liquid?
Yes, that should work.
Around 275 K is what I get.
That's not a terrible approximation, though it is possible they are looking for a more accurate value. I'm not saying they are, just saying it's a possibility.

For a more accurate value, think about how does the 9000 kPa temperature on the chart compare to the temperature at 101 kPa?

p.s to SteamKing: I think this is getting more into your territory than mine.

## What is thermodynamics?

Thermodynamics is the branch of science that deals with the relationship between heat, energy, and work. It studies how these quantities behave and interact with each other in physical systems.

## What is pressure in thermodynamics?

In thermodynamics, pressure is a measure of the force exerted by a gas or liquid on the walls of its container. It is defined as the force per unit area and is typically measured in units of pascals (Pa).

## What are the different types of pressure in thermodynamics?

The two main types of pressure in thermodynamics are absolute pressure and gauge pressure. Absolute pressure is the total pressure exerted by a fluid, including atmospheric pressure, while gauge pressure only measures the pressure above atmospheric pressure.

## How do you calculate pressure in thermodynamics?

The pressure in a thermodynamic system can be calculated using the ideal gas law, which states that pressure is equal to the product of the number of moles of gas, the gas constant, and the temperature divided by the volume of the system. Other equations, such as the Bernoulli equation, can also be used depending on the specific system.

## What factors affect pressure in thermodynamics?

The pressure in a thermodynamic system is affected by several factors, including temperature, volume, and the number of molecules present. Changes in any of these factors can result in a change in pressure, according to the ideal gas law.

Replies
5
Views
1K
Replies
6
Views
4K
Replies
3
Views
2K
Replies
18
Views
3K
Replies
1
Views
1K
Replies
2
Views
3K
Replies
1
Views
2K
Replies
5
Views
2K
Replies
4
Views
3K
Replies
4
Views
4K