How Does a Rising Bubble's Volume Change with Pressure and Temperature?

  • Thread starter Thread starter 6021023
  • Start date Start date
  • Tags Tags
    Gas Ideal gas
6021023
Messages
90
Reaction score
0

Homework Statement


A diver observes a bubble of air rising from the bottom of a lake (where the absolute pressure is 3.50 atm to the surface (where the pressure is 1.00 atm). The temperature at the bottom is 4.0 C, and the temperature at the surface is 23.0 C}.

What is the ratio of the volume of the bubble as it reaches the surface to its volume at the bottom, V2/V1?


Homework Equations


p1V1/T1 = p2V2/T2

V2/V1 = p1/p2 * T2/T1

The Attempt at a Solution



V2/V1 = (3.5)/1 * 23/4

V2/V1 = 20.125
 
Physics news on Phys.org
How would you solve the problem if the temperature was given to you in Fahrenheit?
 
I would convert to K. That gave me the correct answer. Thanks!

Also, there's a second part to this question:

"Would it be safe for the diver to hold his breath while ascending from the bottom of the lake to the surface?"

My first answer would be no, because the solution V2/V1 = 3.74 shows that the volume of air expands more than three times, but I think that the temperature inside the diver should stay the same, and so it won't expand like this. What's the answer?
 
Last edited:
Well, you could assume that the temperature doesn't change from the bottom to the top - you will still get a factor of more than three. What other difference is there between a diver and a bubble? :smile:
 
Thread 'Need help understanding this figure on energy levels'
This figure is from "Introduction to Quantum Mechanics" by Griffiths (3rd edition). It is available to download. It is from page 142. I am hoping the usual people on this site will give me a hand understanding what is going on in the figure. After the equation (4.50) it says "It is customary to introduce the principal quantum number, ##n##, which simply orders the allowed energies, starting with 1 for the ground state. (see the figure)" I still don't understand the figure :( Here is...
Thread 'Understanding how to "tack on" the time wiggle factor'
The last problem I posted on QM made it into advanced homework help, that is why I am putting it here. I am sorry for any hassle imposed on the moderators by myself. Part (a) is quite easy. We get $$\sigma_1 = 2\lambda, \mathbf{v}_1 = \begin{pmatrix} 0 \\ 0 \\ 1 \end{pmatrix} \sigma_2 = \lambda, \mathbf{v}_2 = \begin{pmatrix} 1/\sqrt{2} \\ 1/\sqrt{2} \\ 0 \end{pmatrix} \sigma_3 = -\lambda, \mathbf{v}_3 = \begin{pmatrix} 1/\sqrt{2} \\ -1/\sqrt{2} \\ 0 \end{pmatrix} $$ There are two ways...
Back
Top