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Kinetic Energy for storm/clouds feats

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Ugarik

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It seems that the regular KE formula KE = 1/2mV^2 Ðüð░n not be used in case of expanding clouds (or any expanding mass for that matter)

The reason for this is that not every piece to cloud travels the same distance in the given timeframe. Clouds near the center of a storm need to travel a shorter distance in the same timeframe so you can see that the velocity is not constant for all mass and therefore regal KE can not be used.

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Here's an animation showing that each point of mass of the cloud moves at different velocity. For an average 20 km radius storm that took 2 seconds to fully expand. Mass at the edge the storm is moving at 10 km/s (red point). Blue point in the middle - 5 km/s and green point it the center is not moving at all.

I need to add that the KE formula of expanding mass depends on its shape but since clouds always form a cylinder the KE formula should be KE = mR^2/4t^2. (or just 0.25mV^2)
 
I obviously agree. That means we need to half the standard value for cloud KE on the Cloud Calculations page.
 
Lightbuster30 said:
So, what if you punch/blow a cloud away? Can regular KE still be applied since it isn't an omnidirectional expansion?
Depends a bit on how exactly it looks.

If every part of the cloud is moved the same distance (which usually means the shape of the cloud doesn't really change) then you can do it as before.

If you on the other hand "compress" the cloud to move it out of the way you will need integrals.
 
We don't do KE for expanding cloud formations last I checked. Unless I drastically misremember the last storm thread.
 
Lightbuster30 said:
Compress?
Move the clouds into other clouds, reducing the total volume of clouds.

Idk hard to explain.
 
DontTalkDT said:
If you on the other hand "compress" the cloud to move it out of the way you will need integrals.
That won't effect the formula. It would still be 0.25mV^2
 
Ugarik said:
That won't effect the formula. It would still be 0.25mV^2
It was about clouds that don't necessarily get spread in an omnidirectional fashion. Which part of the clouds move with which speed can be different in this scenario.

Like, for a conical cloud spread for example, where the volume over distance balancing is notably different than in the omnidirectional / cylindrical case.
 
Although, I feel like the most accurate way to find the KE would be by using an integral (like, the speed between the point A and B are variable, and you can say there's another point between them).
 
@DantTalk Yeah made a mistake. I'm this case KE is gonna be much lower because the higher the elemental mass the lower its velocity.

"Like, for a conical cloud spread for example." - Surpisenly, I have the formula for that shape. But I don't think it's important enough to be mentioned
 
DontTalkDT said:
Lightbuster30 said:
Compress?
Move the clouds into other clouds, reducing the total volume of clouds.
Idk hard to explain.
Ah, one more thing: Would this affect storm calcs that involve pulling in a thunderstorm? I doubt they'd be compressed into each other if they were being pulled inwards.
 
Mr. Bambu said:
We don't do KE for expanding cloud formations last I checked. Unless I drastically misremember the last storm thread.
This.

We only really do it for clouds that swirl around in a spiral, or cloud splitting

Then again, in the case where an impact is directed at the sky and the clouds spread outward from that point, this could apply

Also this idea is still weird but I can at least comprehend it with a diagram
 
I don't think any calc would be affected at all. The method OP is proposing to revise was practically nuked months ago.
 
Although Bambu is right, we stopped using these KE methods for expanding clouds, if it do not affect KE by clearing the sky by shear force, it do not really add much.
 
Antoniofer said:
Although Bambu is right, we stopped using these KE methods for expanding clouds, if it do not affect KE by clearing the sky by shear force, it do not really add much.
Did we stop using it?

Maybe I have missed a debate regarding that, but the only thing I remember is that if we don't know how it was accomplished we use the low end. Said low end usually isn't KE, but then again there is probably a non negligible amount of cases where we know how it was accomplished.
 
I also had no idea that KE method was abandoned.

And yes, it does not effect clearing clouds overall
 
Okay. So the current official instructions are fine then?
 
Schnee One said:
We came to the conclusion this was unnecessary since KE got debunked months ago
The pre-calculated KE value in the common results section definitely needs to be changed and so does the corresponding explanation.

Also, as said I don't know about the decision you are referencing. If the practice on cloud calculations changed the Energy Section on the page probably needs to be modified. That being said, I don't really see what is wrong with the current take on KE usage the page explains.
 
@DontTalkDT

Feel free to update it according to your conclusions here.
 
@DMUA: What was debated there should be accounted for at the current version of the page. In fact the page was basically created as a result of that debate IIRC.
 
@Ugarik: When editing the page I noticed that we also care for the opposite scenario: Clouds being pulled in from every direction towards a center point.

Equclouds
Which would mean that in this scenario the AP value is only 1/6th of the usual, which would cause a tier change of the standard value. Is that correct?
 
Yes, the formula is correct but I don't understed why we need one if KE is not allowed anymore.
 
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