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Electroboom: How Right IS Veritasium?! Don't Electrons Push Each Other??
Naej:
--- Quote from: electrodacus on July 12, 2022, 11:57:46 pm ---
--- Quote from: Naej on July 12, 2022, 11:45:04 pm ---I asked the recoil on the bat.
You can compute it with these formulae: https://en.wikipedia.org/wiki/Elastic_collision#One-dimensional_Newtonian
Are you afraid to compute it in case it will lead to more than 2Ws? (coefficient of performance>1)
--- End quote ---
Fine I will waste more of my time most likely.
Vehicle was 300kg driving at 20m/s relative to ground through a space filled with balls traveling in the same direction at just 10m/s
Starting vehicle kinetic energy 0.5 * 300kg * 20m/s2 = 60000Ws
We take 2Ws from the wheel so 60000Ws - 2Ws = 59998Ws
New vehicle speed sqrt(59998 / (300 * 0.5)) = 19.9996666m/s
Bat now has the 2Ws available to hit a ball you mentioned 1000kg ball but it makes no difference for the vehicle as you will see
When the bat hits the ball it will take 2Ws from the ball kinetic energy and transfer to vehicle (ideal case).
--- End quote ---
What's the momentum transferred from the ball to the bat? (It's not 2J, that's energy)
What is the recoil?
You can assume the collision is elastic.
You think you're very good at physics, surely you should be able to apply the formula from wikipedia.
electrodacus:
--- Quote from: dunkemhigh on July 13, 2022, 12:00:01 am ---What is anti-thrust? Is it blowing the wrong way or what? No, forget that - that's just another dead cat you're playing.
You can argue where and how the power is stolen some other message. We don't care if the vehicle is speeding up, down, sideways or outside the wire, but just this once please answer this single thing.
You agree that the turning prop, HOWEVER IT'S POWERED, is producing thrust in the rearward direction?
--- End quote ---
When air particles or 1.2kg balls hit the vehicle they provide the vehicle with kinetic energy when the vehicle hits the balls it loses kinetic energy.
No I do not agree.
At no point the propeller on direct downwind blackbird is producing thrust.
If propeller was say connected to an electric motor and a battery then yes propeller will produce trust.
Direct down wind blackbird has a single source of power than that is wind power so the thrust is done by the air particles hitting the vehicle exactly the same as with a sail vehicle.
The role of the propeller is to create a pressure differential using wind power as input.
If you have two blackbird vehicle identical one in a compressible fluid and one in a non compressible fluid with same density.
What you will observe is that in the non compressible fluid the vehicle will accelerate much faster to some speed lower than fluid speed and remain at that speed constantly.
The other vehicle in compressible fluid will take much longer to get to same speed as part of the energy will be use to create a pressure differential (store energy) and while it took longer it had more time at low speeds to collect/store a lot of energy witch then it uses to exceed wind speed for some limited amount of time.
electrodacus:
--- Quote from: Naej on July 13, 2022, 12:11:45 am ---What's the momentum transferred from the ball to the bat? (It's not 2J, that's energy)
What is the recoil?
You can assume the collision is elastic.
You think you're very good at physics, surely you should be able to apply the formula from wikipedia.
--- End quote ---
Do you need anything other than energy ? I even calculated the speed for you witch is proportional with energy as mass is not changing.
It is like me saying that a DC-DC converter can not output more energy than it gets at the input.
And then to that you first saying that efficiency can be over 100% at which I can not have any other replay than you need to relearn physics.
Then you now ask about things but what about the higher voltage or higher current not realizing that they are not relevant as if one increases the other will need to decrease so that output power is never higher than input power.
You just have no grasp on the concept of energy.
Naej:
--- Quote from: electrodacus on July 13, 2022, 12:40:35 am ---
--- Quote from: Naej on July 13, 2022, 12:11:45 am ---What's the momentum transferred from the ball to the bat? (It's not 2J, that's energy)
What is the recoil?
You can assume the collision is elastic.
You think you're very good at physics, surely you should be able to apply the formula from wikipedia.
--- End quote ---
Do you need anything other than energy ? I even calculated the speed for you witch is proportional with energy as mass is not changing.
It is like me saying that a DC-DC converter can not output more energy than it gets at the input.
And then to that you first saying that efficiency can be over 100% at which I can not have any other replay than you need to relearn physics.
Then you now ask about things but what about the higher voltage or higher current not realizing that they are not relevant as if one increases the other will need to decrease so that output power is never higher than input power.
You just have no grasp on the concept of energy.
--- End quote ---
What you don't realize is that there's a ton of energy in the ball moving at 10m/s, so energy can be conserved even if the car accelerates.
You just have no grasp on the concept of momentum, which is why you can't compute the recoil on the bat.
And it's ok, but you have to believe people who do, and they tell you: the bat recoil gives more energy to the car than what it took from the wheel.
Energy is conserved but you must not forget energy outside the car or else you say wrong things.
gnuarm:
I have learned things from ED. I have learned to spot the fallacious argumentative style used by many in other fields. Rather than discussing the scenario at hand, they divert to discuss a different scenario that is not the same, even if appearing to be the same in some ways. They also confuse the issue, by insisting on certain rules that don't apply in the same way as they were originally conceived. There are other techniques of avoiding the truth.
I have not learned why it is that people, who also have learned what I've learned about this discussion style, are still willing to continue to discuss the issue. Clearly the guy is either A) really, really stupid, or B) enjoying being the mule so much, that he just can't quit.
Which is it, A or B?
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