Nephew middle name is Thunder because he was born during a storm…
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Counts.
In case you dads are short of material.
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The pirate movie joke of similar nature still works imo.
I’m unaware of said jest.
You heard about that new pirate movie?!
It’s rated arrrrgggh!
Oh, man.
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Find it’s good to let stuff out. Keeping it in makes it worse down the road. Hell, I’ve straight wept at work after a disaster… multiple times. It’s better than not letting it out.
Last time was when the woman who I just told had metastatic cancer responded with ‘it must be really hard for you to tell people things like this’. Think I told that story.
It’s the people who see that kind of thing and don’t react that I don’t trust.
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My favorite dad joke admittedly doesn’t work as well in writing, but is:
Why does Ariel wear seashells?
Because the D shells don’t fit.
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Of all the people that have crushed any shred of optimism out of me, Obama tops the list.
57% of dads are the best. Not bad!
That cartoon is gonna stay with me.
As some of you may have noticed, I’m more open than most to nutty possibilities like cold fusion and alien visitors and shit. This is just as wild in it’s own way. The claim is that this wind-car can accelerate to velocities higher than the wind propelling it.
Sean Carroll also involved. Barely gets a mention.
My hunch is the names Bernoulli and Einstein will come up yet again.
I like that this is an argument that should be able to be settled, but experience following many similar situations says neither side will budge very easily.
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I was like “Huh? This is trivial, fast yachts do it all the time” but clicking through to the article, the claim is actually this, my emphasis:
that it can travel directly downwind faster than the wind itself, using no acceleration source other than wind.
Kind of amazed that someone is willing to bet on something so obviously impossible. If you’re moving downwind at the same speed as the wind, the wind cannot be exerting any force on you. It doesn’t matter what super sick propeller design you have when there’s no force acting on it.
I don’t know anything about boats but you’re saying they can reach speeds greater than the component of the wind velocity parallel to their direction of travel, right? I guess that’s because the sails are oriented perpendicular to the direction of maximum wind velocity while the boat actually moves at some angle to that? I wouldn’t have anticipated that but yeah, that’s not so amazing.
I’m surprised Veritasium is doing it because he’s so likely to be embarrassed if it turns out they didn’t measure the vehicle/wind speeds or directions correctly or there’s some other simple explanation. He’s Australian. You should be on his side!
This is interesting to me because it’s similar to other situations like cold fusion where there are observations by competent people that haven’t been shown to be in error. The difference being that here it should be relatively easily decidable.
This is far out there but it’s enough of a mystery that I’m not going to call the guy an idiot. Besides, he’s friends with Natalie Tran. I’ll wait to hear what she says before passing judgment.
Is there any clearer sign of a deplorable than Billy Big-Mouth Bass?
I watched his youtube and he talked about sailboats. They actually do go faster than the wind in the direction of the wind. My mind is blown in more ways than one.
The explanation offered is that the sail acts like an airfoil, with the lift force going into pushing the boat forward. But if that’s the case, then the propeller on the car acting in a similar way doesn’t seem so far-fetched.
Of course there’s still the small problem that nobody has a good explanation of how airfoils work. At least I was right that Bernoulli and Einstein would pop in here.
The sails generate lift, like an airplane wing, which drags the boat forward. The force is diagonal but stuff like keels arrests sideways movement and only the forward velocity takes effect. The sort of catamarans they sail in the America’s Cup can reach nearly triple the speed of the wind.
It seems like maybe I’m wrong about this wind-car thing, I went down a rabbit hole of reading about it. It doesn’t have a propeller driven by the wind like I was imagining, it hooks a propeller up to the wheels and drives it from the forward movement of the vehicle. The initial velocity is provided by the wind and the propeller harnesses some of that energy to push back against the wind, driving the vehicle faster. This has the smell of perpetual-motion about it, but apparently you can do this. In a sea of incomprehensible explanations, this analogy was useful:
You have a robot on an airport style people-mover which moves at 10mph. The robot can use 1 watt to move forward at 2mph on the mover, making a total ground speed of 12mph. To keep this up, it puts out a generator wheel to contact the ground. This wheel sees a total speed of robot_speed + mover_speed. The extra force of this generator rolling along the ground is going to make it harder for the robot to crawl forward, which is going to slow its crawl. What makes this work out is that the generator is using the total_speed, but the robot only needs to produce robot_speed. So they will come to an equilibrium where the robot slows down until the energy its using to move forward is equal to the energy produced by the wheel. Even in a very inefficient setup, the wheel will be producing some power since its moving at at least 10mph, and the robot can use that to make some forward progress.
If the people-mover stops, then you’re back to the standard perpetual-motion situation where you’re trying to power a car from a generator based on the wheel speed of the car - doesn’t work. When the people-mover is going, however, you have a base wheel speed that’s powered externally, and that’s what makes it work.
Now on to the wind. The people-mover is the wind, the robot is the vehicle. The robot’s wheels are the propeller, worming its way slowly along the wind (i think worming slowly through the wind as a worm gear would is easier to picture than the aerodynamics). The propeller is powered off the vehicle’s wheels (as the robot was powered off its ground-touching generator).
With the wind situation it is very similar, only it is easier to imagine losses and inefficiencies (for the robot it is easy to stick to and crawl along the people-mover, far easier than to grab onto the wind!).
How will the power we take from the wheels increase our speed past the speed we would have been without taking that power, you ask?! Go back to the people-mover example! We’re taking power from the sum of the wind just regularly pushing us along, plus the extra speed we get by clawing our way forward through the wind with the prop, but we only have to put that power back into the extra bit of speed from the prop.
Maybe it will take off 
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