What are the differences between regimes I and II in drag forces?

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Regimes I and II in drag forces relate to different flow conditions characterized by Reynolds numbers. Regime I, associated with low Reynolds numbers, is governed by Stokes' law, where drag is proportional to velocity. In contrast, Regime II applies to high Reynolds numbers, where drag increases with the square of velocity, typical in turbulent flow. The discussion highlights the importance of understanding these regimes in the context of laminar versus turbulent flow. Additional resources, such as Wikipedia, provide further clarification on these concepts.
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So I was looking at MIT iTunes U physics videos, and the professor talked about regimes I and II in the video about drag forces. I think regime I has to do with the temperature of the medium and regime II has to do with the density. But, I cannot find that information in my 1st semester physics textbook. Nor can I find such info using Google (perhaps I'm using the wrong search terms?:rolleyes:). Can anybody provide me with links to websites containing such stuff in them?
Thank you very much! :D
 
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I've never heard of this terminology before. It sounds very odd... I'd need to see the context of how they are using these words.
 
There is the laminar flow regime vs. the turbulent regime. There is also the subsonic flow regime vs. supersonic. You should be able to tell which two are being distinguished from the context.
 
Phrak said:
There is the laminar flow regime vs. the turbulent regime. There is also the subsonic flow regime vs. supersonic. You should be able to tell which two are being distinguished from the context.

Ok, thanks for the info! :smile:
 
Both regimes are discussed here:
http://en.wikipedia.org/wiki/Drag_(physics )
Low Reynolds number drag is also called Stokes law. High Reynolds number drag (Re > 1000) corresponds to a force that is proportional to square of velocity, like an automobile at highway speeds.
 
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