I Equation for power required to overcome drag

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    Drag Power
AI Thread Summary
The discussion centers on the validity of a specific drag power equation, with participants questioning its assumptions and definitions. The equation's variable "v" is defined as the speed of the fluid relative to the object, which some participants dispute. There is a call for references from proper textbooks to support differing viewpoints, but no consensus is reached on the equation's correctness. The conversation also touches on previous threads and moderation issues, indicating ongoing contention around the topic. Ultimately, the thread is closed again for moderation, suggesting unresolved disagreements.
electrodacus
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Here is the link to the equation I consider to be correct https://scienceworld.wolfram.com/physics/DragPower.html
Is anyone disagreeing with that and if so can you provide a link or screenshot from a proper textbook ?
The v in that equation is defined as speed of the fluid relative to the body.
 
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electrodacus said:
Here is the link to the equation I consider to be correct https://scienceworld.wolfram.com/physics/DragPower.html
Is anyone disagreeing with that and if so can you provide a link or screenshot from a proper textbook ?
The v in that equation is defined as speed of the fluid relative to the body.
It is the drag force multiplied by the speed which makes it the drag power. If drag power is what you're looking for, it is correct.
 
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Thread closed temporarily for Moderation...
 
electrodacus said:
Here is the link to the equation I consider to be correct https://scienceworld.wolfram.com/physics/DragPower.html
Is anyone disagreeing with that and if so can you provide a link or screenshot from a proper textbook ?
The v in that equation is defined as speed of the fluid relative to the body.

Thread reopened, sort of...

Is this related to your two previously closed threads, and your temporary vacation from PF?
 
berkeman said:
Thread reopened, sort of...

Is this related to your two previously closed threads, and your temporary vacation from PF?

The question is as simple as stated. I asked if that is the correct equation ?
I think it is but I can always be wrong.
 
electrodacus said:
The question is as simple as stated. I asked if that is the correct equation ?
I think it is but I can always be wrong.
No. Just like a traffic cop stopping a car for rolling through a red light, the Mentors monitor your posting history and use it to Moderate future posts. We do not allow restarting locked threads, even if you initially try to hide your motives.

electrodacus said:
Is anyone disagreeing with that and if so can you provide a link or screenshot from a proper textbook ?
Under what assumptions? What are the assumptions behind that web page formula?
 
berkeman said:
Under what assumptions? What are the assumptions behind that web page formula?
Not everybody seems to agree with that equation.
Maybe there is something that I'm missing or not understanding so I want to make sure that is the correct equation if I want to calculate the power needed by an object to overcome drag (any object traveling through a fluid).
The discussion on this thread will not go any further than confirming that equation is correct.
 
Last edited by a moderator:
electrodacus said:
Not everybody seems to agree with that equation.
Who are the people who don't agree and what do they say? We can't have a proxy debate with people who aren't in the thread and are not cited.
The discussion on this thread will not go any further than confirming that equation is correct.
The answer was given in post #2.
 
russ_watters said:
Who are the people who don't agree and what do they say? We can't have a proxy debate with people who aren't in the thread and are not cited.

The answer was given in post #2.

Yes post #2 has provided the answer that I consider to be correct thus I used the Like button for that post.
Even yourself disagreed with this equation in the past.
The claim if I remember correctly was that
- speed in that equation was the object/vehicle speed relative to ground times drag force
- while I was claiming that speed is the fluid speed relative to the object/vehicle.
 
  • #10
electrodacus said:
Even yourself disagreed with this equation in the past.
The claim if I remember correctly was that
- speed in that equation was the object/vehicle speed relative to ground times drag force
Neither of those is true.

So, this is a continuation of your prior threads on DWFTTW, right? If not, where are we going from here?
 
  • #11
electrodacus said:
Yes post #2 has provided the answer that I consider to be correct thus I used the Like button for that post.
Even yourself disagreed with this equation in the past.
The claim if I remember correctly was that
- speed in that equation was the object/vehicle speed relative to ground times drag force
- while I was claiming that speed is the fluid speed relative to the object/vehicle.
https://www.google.com/url?sa=i&url...ved=0CA8QjRxqFwoTCIi7janK9fsCFQAAAAAdAAAAABAH
 
  • #12
It gives me an error as video unavailable.
 
  • #13
russ_watters said:
Neither of those is true.

So, this is a continuation of your prior threads on DWFTTW, right? If not, where are we going from here?
This is strictly about this equation. It is one of the more important equations in physics in my opinion.

You will need this equation if you want to build a wind turbine or if you want to calculate the power needed for a vehicle of any type to overcome drag to name just a few examples for the use of this equation.
 
  • #14
electrodacus said:
It gives me an error as video unavailable.
It's the theme music from the movie Jaws. It's meant to signify that you probably should not have tried to go for a swim at the same beach where you were bitten twice before...
 
  • #15
berkeman said:
It's the theme music from the movie Jaws. It's meant to signify that you probably should not have tried to go for a swim at the same beach where you were bitten twice before...
:) funny.
But I do not think it applies to this case. I do not see how I was bitten ? To me it looks more like I was banned because people were thinking I invented or misused equations.
There is also a calculator that properly applies this equation correctly https://www.electromotive.eu/?page_id=12&lang=en
 
  • #16
electrodacus said:
To me it looks more like I was banned because people were thinking I invented or misused equations.
Thread closed again temporarily for Moderation. I will try to find your quote in your previous threads where you acknowledged that the video demonstrations were real. Give me a day or so please...
 
  • #17
For if @berkeman chooses to re-open the thread:
electrodacus said:
This is strictly about this equation.
Then since the question about the equation has been answered, the thread is finished, right?

[Edit] @berkeman has decided to keep the thread closed.
 
Last edited:
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