The acceleration of a bubble in water

  • #1
17
0

Main Question or Discussion Point

Hi,

I have a question about a rising bubble.
I read that the initial acceleration of a bubble (with negligible mass) in water is 2g, where g is the gravitational acceleration. I understand that if a bubble rise then the water move around it, but I can't derive this equation.
Could someone help me out?
 

Answers and Replies

  • #2
BvU
Science Advisor
Homework Helper
2019 Award
13,039
3,014
I see no reasonable argument for this statement.
What is your reference and what does it say to justify such a claim ?
 
  • #3
ZapperZ
Staff Emeritus
Science Advisor
Education Advisor
Insights Author
35,538
4,312
I read that .......
This requires a clear reference to the source.

Zz.
 
  • #4
17
0
  • #5
hilbert2
Science Advisor
Insights Author
Gold Member
1,342
415
Looking at the pdf file, the problem 52 seems to assume that the liquid has no viscosity, which isn't true in general.
 
  • #6
BvU
Science Advisor
Homework Helper
2019 Award
13,039
3,014
I did find a 2g here but don't see an explanation. And here it gets worse: 3.3 g ! But they do show how the 2g comes about in section 2 (of course :smile:). So your derivation is available.

Must admit I learned to be a bit more open-minded: at first I didn't believe more than g is physically possible....

This one below ? I don't see it. But then again: you say the answer is 2. So: follow the steps and see where you end up
Help us help you and post your working ...

upload_2018-6-26_17-57-58.png
 

Attachments

  • #7
17
0
Thanks, I'm not certain that I can understand your reference because that seems very complicated but I'll try
 

Related Threads on The acceleration of a bubble in water

  • Last Post
Replies
4
Views
703
  • Last Post
Replies
1
Views
545
  • Last Post
Replies
6
Views
1K
  • Last Post
Replies
6
Views
3K
  • Last Post
Replies
4
Views
6K
  • Last Post
Replies
3
Views
2K
Replies
13
Views
1K
Replies
1
Views
507
Replies
1
Views
568
Replies
3
Views
2K
Top