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So Navy's of tomorrow will have their ships covered in mirrors. Now, someone tell me why this won't work... because it seems like a really obvious way to divert a laser beam.
Because a mirror does not reflect 100% of the energy, some will be absorbed, thus the laser will eventually burn through it. Super efficient mirrors are easy counter anyway, just lob some "buckshot" at the target to shatter the mirrors, then burn the ship up with the laser
So while the vehicle might be traveling faster than the wind in burst, it won't get you any place faster than the next wind powered vehicle.
. The vehicle accelerates to a a speed faster than the wind, then stays at that speed forever (as long as the speed of the wind is constant) and does not oscillate. It really will get you to your destination faster than e.g. a balloon traveling at precisely the speed of the wind.
There is a feedback loop, but it works like this: there is a wind velocity X, and a stable velocity Y for said X, where Y>X (for a properly designed vehicle using this technique). If the velocity momentarily exceeds Y, the friction losses of the wheels will be greater than the gain in push from the fan, and the car will slow down. If the velocity momentarily drops below Y, the friction losses of the wheels will be lower than the push from the fan, and the car will accelerate forward. It stabilizes at Y, faster than X. The feedback loop keeps it at that stable Y.
I don't believe it can, no matter how stable, energy in will never be greater than the energy out. A balloon wouldn't be a good example, another vehicle with just sails to catch the wind running side by side would be the best comparison. Basically, the sail vehicle would start off much quicker and be far ahead of this vehicle before the faster-than-wind vehicle got up to speed. Afterwards, it would just be an infinite slope towards the finish. I think what everyone misses here is the time part. It may go faster than the wind at some point, but it won't continue that way forever nor can it make up for the time. Basically the vehicle is just trading out time for speed. The mystery would lose a lot of luster if they did the same run with two side by side vehicles in a race (one straight sail, the other being the faster-than-wind vehicle). All I've seen for video footage is a single vehicle run, which takes the faster-than-wind part out of context and makes it appear to be perpetual energy, which it certainly is not. We all know that, but the single vehicle run is what gets everyone in an uproar over the laws of physics.
Here is what bothers me about this whole thing.
Although I believe it is theoretically possible, there is a certain whiff of woo about the experimenters. I'm not even saying they didn't achieve their objective--I'm just saying there are a couple of things about the experiment, especially with regard to the stored energy issue, that nearly broke my woo-meter.
From the official rules:
Energy shall not be accumulated and later used for propulsion of the yacht or to operate the controls of the yacht.
It seems to me that this would preclude the use of massive windmills (i.e., flywheels), such as the one on the craft. Later, the rules specifically prohibit flywheels:
It is not permissible to use stored energy to propel the yacht or operate its controls. This might includes things like compressed gas, stressed springs, batteries, capacitors and flywheels. This includes energy stored before a run or during a run. No pumps, generators or mechanical devices that are intended in part or whole to provide energy to storage devices are permitted. Stored energy in the form of momentum of the yacht, its wheels or other **normally moving** or flexing parts of the yacht is allowed. These forms of stored energy are inherent in the operation of the yacht and either do not add energy useful for increasing the speed of the yacht or **do so in a trivial way**.
(emphasis mine)
What constitutes a "normally moving" part of the yacht? What constitutes a "trivial" use of stored energy to increase its speed?
That's I thought to, but here is how it works with laymen terms for all (including myself). The vehicle is simply geared in a way that the propeller will move air from the front of the vehicle to the back faster than the air moves from the front to the back. So if the vehicle is moving 5 mph forward, the propeller is trying to force air in the same direction at 10 mph. What happens is, as the vehicle is being pushed by the wind, the vehicle moving forward is building kinetic energy. Eventually the vehicle reaches the maximum speed that the wind is able to push the vehicle. At the same time, the ground is supplying energy to the propeller to push the vehicle faster. So what is really happening is a waveform; the vehicle moves with the wind, then moves faster than the wind, then slows down, gains more energy, moves with the wind, faster, repeat, etc. Basically if you compared this vehicle side by side with another one with just sails for example, the vehicles would reach the same destination at the same time overall. So while the vehicle might be traveling faster than the wind in burst, it won't get you any place faster than the next wind powered vehicle.
Booze is the answer. I don't remember the question.