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You failed to read your own article which actually supports what I was saying. This puts you in quite a vulnerable state:
"Sailboats utilize both true wind and apparent wind. One force pushes the sailboat, and the other force pulls, or drags it forward."
Not only is a sailboat being pushed by wind, it's also being pulled by wing (the drag I mentioned in my previous post).
You either don't understand what you're talking about or you also failed to watch the video. There's no dragging wind or air displacement involved in the bet.
You failed to read your own article which actually supports what I was saying. This puts you in quite a vulnerable state:
"Sailboats utilize both true wind and apparent wind. One force pushes the sailboat, and the other force pulls, or drags it forward."
Not only is a sailboat being pushed by wind, it's also being pulled by wing (the drag I mentioned in my previous post).
You either don't understand what you're talking about or you also failed to watch the video. There's no dragging wind or air displacement involved in the bet.
Still wrong.
A sailboat (or ice boat) travels fastest at an angle to the wind. The component of its velocity that is parallel to the wind IS smaller than the wind velocity, as the sails are not 100% efficient and there is hydrodynamic drag. However, the boat is traveling at an angle to the wind. Its total velocity is the hypotenuse of a right triangle, one of whose legs is its velocity parallel to the wind, and the other leg is its velocity perpendicular to the wind. If you'll recall your eighth grade geometry, the hypotenuse of a right triangle is LONGER than either leg. Remember that guy called Pythagoras.
The more effective the keel of a sailboat at preventing sideslip, the greater the angle to the wind at which it can sail. The greater the angle, and the more efficient its sail plan, the larger the hypotenuse of the triangle is compared to the leg that's parallel to the wind.
Read up on vectors.
A note of caution, don't let yourself get caught up in "apparent wind" and so on; this is an artifact of the moving frame of reference on the boat. Consider yourself in a fixed frame of reference, hovering above the boat as it moves, to understand more easily.
A sailboat (or ice boat) travels fastest at an angle to the wind. The component of its velocity that is parallel to the wind IS smaller than the wind velocity, as the sails are not 100% efficient and there is hydrodynamic drag. However, the boat is traveling at an angle to the wind. Its total velocity is the hypotenuse of a right triangle, one of whose legs is its velocity parallel to the wind, and the other leg is its velocity perpendicular to the wind. If you'll recall your eighth grade geometry, the hypotenuse of a right triangle is LONGER than either leg. Remember that guy called Pythagoras.
The more effective the keel of a sailboat at preventing sideslip, the greater the angle to the wind at which it can sail. The greater the angle, and the more efficient its sail plan, the larger the hypotenuse of the triangle is compared to the leg that's parallel to the wind.
Read up on vectors.
A note of caution, don't let yourself get caught up in "apparent wind" and so on; this is an artifact of the moving frame of reference on the boat. Consider yourself in a fixed frame of reference, hovering above the boat as it moves, to understand more easily.
Actually you're the one that is very wrong... in multiple ways. But the most important part is that the wind on the car is only coming in one direction (parallel to car and not at an angle). Your triangle example has the boat going in another direction than downwind.
Actually you're the one that is very wrong... in multiple ways. But the most important part is that the wind on the car is only coming in one direction (parallel to car and not at an angle). Your triangle example has the boat going in another direction than downwind.
Yes, because that's the direction that boats sail fastest. They don't sail fastest downwind. If the boat is headed directly downwind it's impossible for it to go faster than the wind velocity. In fact, directly downwind, it's impossible for it to equal wind velocity, because sails aren't 100% efficient and because there's drag on the hull against the water.
If the boat is sailing with the wind on its quarter, its velocity in the wind direction is still less than the wind velocity, but it also has a component perpendicular to the wind velocity, and its total velocity is the sum of those two vectors. Being a vector sum, it's the root sum of squares. If the sail plan is efficient (so its parallel velocity is a large fraction of the wind velocity), and if the keel is effective at minimizing sideslip (so the angle between the direction of the boat and the angle of the wind is "large", then the total velocity of the boat will exceed the wind velocity. Just draw it out and you'll see.
Ice boats can exceed the speed of water boats for a given wind speed, as their runner blades are extremely efficient keels, and the drag of their runners on ice is very low.
I should point out that if you want to cavil at "vehicle" being used for a boat, there are vehicles that are built along the plan of the iceboat, but use wheels and run on pavement. They have many of the same characteristics of iceboats - I expect they don't reach the same speeds due to the increased rolling resistance of tires and wheels compared to runners on ice, but I'm sure they too can exceed wind velocity in their groundspeed, depending on how the wind's quartering to their direction.
The sailboat is an interesting example - and demonstrates that yes, it's a matter of extracting energy from the wind (or rather, the speed difference between the two mediums that the boat touches) rather than merely being pushed along. At a suitable wind angle and with an aggressive sailboat, the speed component directly upwind or downwind can be higher than the wind speed. Sailboat racers with good instrumentation will talk about "velocity made good".
The dead-downwind example is a bit different, though. Now you can't use your sails as a lifting surface and they may as well be pieces of plywood.
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