Fizica navigației | KQED QUEST

46 thoughts on “Fizica navigației | KQED QUEST”

1. Taking my 1st sailing lesson today and wanted a head start😁

2. Lift has nothing whatsoever to do with the force acting on the sail. Lift is generated by photons eminating from the ground. The force acting on the sail is purely kinetic and is a function of the angle of attack… Basic stuff

3. Im here cuz of SV Delos ;,)

4. About to buy a lil sailboat with my mate. Figured I should learn something first

5. This video seems to be about sailing. ⛵

6. that did not help explain how it works… i would assumed they woud use computer 3d animation to explain it .. justa a baot in the water with arrow pointing isnt enough

7. My takeaway is that the keel does more than keep the boat right side up.

   Everyone else arguing correct physics and history about sailing sound like they’re arguing about the sport of golf.

8. I was watching Guardians Of The Galaxy 2 when all of the sudden I had an intrusive thought about how ships sail, so here I am.

9. Go NorCal !!!!

10. Laminar flow and boundary layer is how it works!

11. 2 minutes of information spread throughout 9+ mins.

12. "The following KQED production was produced in high definition" -> check quality setting and found 360p XD

13. "The following production was produced in high definition."
    >it's 360p

14. This video kindof sucks, didn't grasp the concept

15. nasa scammers.. sigh

16. "the following was produced in high definition" – best availability… 360p….

17. Watched nine-and-a-half minutes. Still waiting for them to explain what the front sail does.
    Any moment now would be fine…

18. What do you think a 1600's pirate would think if someone time-traveled with a modern yacht, and sailed circles around him… literally… ??

    He'd probably tweet mind equals blown… cuz ya know … twitter was definitely a thing back then ^‿–

19. They are just showing real videos and telling stories over them. You won't learn any physics like that. They need to show you force diagram. One big apparent failure is not demonstrating how a flat sheet is being compard to the wing of a plane, which is not flat.

20. Very silly history. Square rig boats also had lift producing sails and they did not go slow. Old clippers would go very fast considering the time in history.

21. I wonder how the keel creates lift.

22. Tried to watch this in order to understand vectors but get visual examples of aerodynamics, bernoulli's principle, and pressure instead. Not enough to be called educational material, more on commercial and entertainment purposes but at least it gave me a general understanding on how boats fight against wind resistance when travelling against the wind.

23. It's was alright but not needing exposed to NASA 🐍

24. Heavy hitters

25. Sailing is like walking or chewing gum. It becomes a natural 'feel'. Just instinctive. Don't overthink it.

26. when 360p was called hd

27. I didn't understand shit

28. Why does the air/liquid accelerates going around the curve surface? The reason given thus far is that it needs to catch up with the flow on the other side. Why?
    By the way when you blow on one side of the paper, the paper doesn't have to be curved to move across the direction of the flowing air. A flat piece of paper will do. A curved paper first wants to straighten out.

29. This item does not explain sailing very well ,and is confused and over complicated. I have taught thousands of people to sail professionally at a much more practical level . I also won championships and crossed oceans using the Trade Winds !
    Fundamentally imagine the blackboard with the wind from the top. Draw on a boat shape and a curved sail in beam reaching position , The physics is that the sail curves the wind and the big arrow is the push mostly forward,
    Square rigs were for Tea Clippers. The local fishermen would use a sloop rig. And the Romans would use Galley Slaves for ultimale upwind performance ….

30. The two happiest days of a boat owners life?

31. Shaking my head every time someone invokes Bernoulli – https://youtu.be/yqwb4HIrORM?t=239 "generate higher velocities on one side … consequently lower pressure … pressure difference, and that leads to force" – as a *cause* instead of an effect. They never explain what generates the higher velocities: in a venturi, there is a area restriction to increase velocity, but in sailing there is no nearby wall to restrict the area; the thickness of the sail is so small that the "flow takes longer distance on the lee side so airflow must be faster" argument must also be bogus. Note that we can also sail with a flat (symmetrical) plate as a sail (also note that the keel/centerboard, the underwater "sail," is already symmetrical), so explanation that relies on the curvature of the sail does not account for the basic mechanics.

    Momentum transfer of diverted airstream (and water stream) is a much simpler explanation: d(mV)/dt = F.

32. Dynamical man!

33. Physics explanation is wrong. Bernoullies effect produce less than 1% of the lift (You don't believe me make the math. Or just look at the plain wing of the first ever airplane. Or just look at the plain wing of any paper airplane). The real lift is produced by air deflectation

34. Is Paget Brewster the narrator?

35. i like to be the youngest comment

36. Even old sailers at old times know the clever idea of sailing ⛵ against wind . Actually sailing teach aviation this principle not the vice versa .
    Aviation learn this early from sailing field.. the first people at old times that discover this theory and apply it is the ARAB sailer this fac is documented and known historically .

37. Down wind,just bag the wind, upwind,pull the sails in till they just stop fluttering on the leach,, YOUR SAILING!!!!!!!!!!

38. Shouldn't the force of keel be perpendicular to the boat (or slightly aftward) at 5:44 ?

39. Lift forces due to the acceleration of air across the curved surface is overstated. Stop abusing Bernoulli, look to Newton — there is a huge redirection of air mass in a new direction creating forces in the opposite direction (forward).

40. Square-rigged ships COULD sail
    into the wind! Just not very well.

    Channel 9, maybe a wee bit of
    research would be handy.

    steve

41. I was told low pressure, not lift is more accurate.

42. 3:53 Oh I see now…makes perfect sense😂

43. Triangular sails exists for hundreds of years xD That was the most idiotic piece of information I've seen on an supposedly informative video. Shameless.

44. 𝐩яⓞ𝓂𝓞Ş𝐦 😊

45. Calculation in Science

46. Hey this announcer sounds like the young lady at NASA that is in the JWST productions.

Comments are closed.