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Electroboom: How Right IS Veritasium?! Don't Electrons Push Each Other??

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Alex Eisenhut:

electrodacus:

--- Quote from: Naej on July 11, 2022, 10:30:26 pm ---So you disagree with air mass flow approximately equal to area * density * relative speed?
Interesting. Why? What's your opinion on the subject and can you substantiate it?

It applies to all vehicles where you have air flowing through an area. So don't apply this to sails.

--- End quote ---


I can write the equation less simplified like this
Pw = (area * air density * (wind speed - vehicle sped)) * (wind speed - vehicle speed)2 * 0.5  =  0.5 * air density * area * (wind speed - vehicle speed)3
Can you recognise the mass flow ?

This equation (witch is the correct one) applies to all vehicles including those using sails or wind turbines or anything else that you may think off. It is universal.

Naej:

--- Quote from: electrodacus on July 11, 2022, 11:22:07 pm ---
--- Quote from: Naej on July 11, 2022, 10:30:26 pm ---So you disagree with air mass flow approximately equal to area * density * relative speed?
Interesting. Why? What's your opinion on the subject and can you substantiate it?

It applies to all vehicles where you have air flowing through an area. So don't apply this to sails.

--- End quote ---


I can write the equation less simplified like this
Pw = (area * air density * (wind speed - vehicle sped)) * (wind speed - vehicle speed)2 * 0.5  =  0.5 * air density * area * (wind speed - vehicle speed)3
Can you recognise the mass flow ?

This equation (witch is the correct one) applies to all vehicles including those using sails or wind turbines or anything else that you may think off. It is universal.

--- End quote ---
So you agree with the mass flow equation? (Except that you invented a negative mass flow  :-DD )
But then you changed the kinetic energy part? For some reason.
Your formula is correct in the car reference frame. And in the car reference frame the car has no kinetic energy. Zero, nada, nothing. However the ground is FULL of kinetic energy.
It's much more intuitive to look in the ground reference frame, where wind power is what I said and the car has kinetic energy. And the car can get energy from the wind.

electrodacus:

--- Quote from: Naej on July 11, 2022, 11:31:40 pm ---So you agree with the mass flow equation? (Except that you invented a negative mass flow  :-DD )
But then you changed the kinetic energy part? For some reason.
Your formula is correct in the car reference frame. And in the car reference frame the car has no kinetic energy. Zero, nada, nothing. However the ground is FULL of kinetic energy.
It's much more intuitive to look in the ground reference frame, where wind power is what I said and the car has kinetic energy. And the car can get energy from the wind.

--- End quote ---

You do have a big problem understanding energy conservation so not quite sure how I can explain anything to you as all of physics depends on understanding this first law of thermodynamics.
Saying things like more than 100% efficiency is possible and "However the ground is FULL of kinetic energy."
Changing reference frames if done correctly will not change anything so same result no matter what reference frame you use.
So you can not say that my equation is true in some reference frame but not in another. It is either true in all reference frames or in none.

As for negative sign for power or flow it just shows the direction.
When you charge a capacitor you have one direction for current and opposite direction when discharging. You need to differentiate between the two with a sign.
Here you are either charging or discharging the stored kinetic energy of the vehicle.

A vehicle stationary relative to ground will have zero potential energy relative to ground but if there is wind it will have some potential energy relative to air.
And at the other extreme a vehicle traveling at wind speed will have zero potential energy relative to air but some potential energy relative to ground based on speed relative to ground and the mass of the vehicle.

Without using energy storage the vehicle (no matter the design) can only have a speed relative to ground between zero and wind speed and nothing outside this range so no negative speed (direct upwind) and no higher than wind speed.

Naej:

--- Quote from: electrodacus on July 11, 2022, 11:51:25 pm ---
--- Quote from: Naej on July 11, 2022, 11:31:40 pm ---So you agree with the mass flow equation? (Except that you invented a negative mass flow  :-DD )
But then you changed the kinetic energy part? For some reason.
Your formula is correct in the car reference frame. And in the car reference frame the car has no kinetic energy. Zero, nada, nothing. However the ground is FULL of kinetic energy.
It's much more intuitive to look in the ground reference frame, where wind power is what I said and the car has kinetic energy. And the car can get energy from the wind.

--- End quote ---

You do have a big problem understanding energy conservation so not quite sure how I can explain anything to you as all of physics depends on understanding this first law of thermodynamics.
Saying things like more than 100% efficiency is possible and "However the ground is FULL of kinetic energy."

--- End quote ---
Alright what's the kinetic energy of 1kg of ground if the car is moving at 10 m/s ?

--- Quote from: electrodacus on July 11, 2022, 11:51:25 pm ---Changing reference frames if done correctly will not change anything so same result no matter what reference frame you use.

--- End quote ---
True. But you're so confused by the car reference frame that you don't understand that ground has kinetic energy in this frame.
So it's better to stay in the ground reference frame.

--- Quote from: electrodacus on July 11, 2022, 11:51:25 pm ---So you can not say that my equation is true in some reference frame but not in another. It is either true in all reference frames or in none.

--- End quote ---
Wrong. The kinetic energy in air depends on the speed, which depends on the reference frame.

--- Quote from: electrodacus on July 11, 2022, 11:51:25 pm ---As for negative sign for power or flow it just shows the direction.
When you charge a capacitor you have one direction for current and opposite direction when discharging. You need to differentiate between the two with a sign.
Here you are either charging or discharging the stored kinetic energy of the vehicle.

A vehicle stationary relative to ground will have zero potential energy relative to ground but if there is wind it will have some potential energy relative to air.
And at the other extreme a vehicle traveling at wind speed will have zero potential energy relative to air but some potential energy relative to ground based on speed relative to ground and the mass of the vehicle.

--- End quote ---
Sure, if you have a flow of -1 capacitor/s containing 1J then you have -1W of capacitor power.

But then it means that with -1000W of wind power, I can take 300W with a wind turbine. Because the sign does not matter.  8)

--- Quote from: electrodacus on July 11, 2022, 11:51:25 pm ---Without using energy storage the vehicle (no matter the design) can only have a speed relative to ground between zero and wind speed and nothing outside this range so no negative speed (direct upwind) and no higher than wind speed.

--- End quote ---
You must have asserted this 500 times without any proof, but it's still wrong.

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