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  • Can you fix that?

  • Hey, that was a hard run because, uh, this balls a little bit magic.

  • It's got a bit of string glued to the left side of it to make the ball curve to the left.

  • What is that?

  • That's because air that's flowing from the front of the ball around to the back and count it's the same becomes turbulent and turbulent.

  • Air is known to stick to the ball longer than smooth laminar flow.

  • The air is deflected this way to the right, on the ball, and therefore there's a force on the ball to the left.

  • And so it curves.

  • So I think this is quite a light.

  • Bulbs heart curves along like uh, but on a cricket ball, the seam isn't on one side, it seems down the middle correct.

  • It's spinning in such a way that that seems inclined at an angle to the direction of motion of the ball, in which case air coming towards the ball will flow smoothly around the Smith side and separates from the ball air flowing on the rough side.

  • The same side becomes turbulent as soon as it encounters.

  • That same gets deflected to the left, and therefore the ball gets deflected to the rock.

  • So you basically make a rough side using that seem by angling the scene with a cricket ball cricket ball.

  • Or you can have a wrapping of Smith's side because as time goes on during the game, one side gets rougher than the other.

  • The players maintain the smooth side by polishing it wherever a ziff there, scratching themselves right?

  • Uh, and then you don't really need the same have that effect because the effect is just a rough sadness.

  • Minutes or so a bowl always swing towards the rough side.

  • It does.

  • But how does someone swing a baseball then?

  • That relies on the Magnus effect normally, so that spin is about a vertical axis ally that curve to the left or curve to the rides.

  • A curveball?

  • Exactly, however, there's a pitch ball.

  • Nine.

  • It's a scuff bowl.

  • The people that like to know about cars, it's illegal.

  • And if you're roughing up one side of the ball surreptitiously without anybody married to singer on, then toss it.

  • It will have a long way, just like the cricket ball curve towards the rough side.

  • Correct.

  • However, there's an effect discovered just this.

  • Yeah, which is fairly obvious when you think about it.

  • You can have a smooth patch on a baseball, but I mean, the seems seems to be symmetric everywhere.

  • So how can you really have a smooth patch?

  • What you do there is to make sure that access passes through a spot, which is a large distance from the same.

  • In other words, right about that, about one inch away from the same.

  • And if it right tights about that access, then you've got a big spot that's always smooth on that side.

  • Got a smooth spot as opposed to a rough spot, and so it swings away from this move spot that does, and I can show you that in slow motion.

  • So you've tried this out.

  • One of your police siren.

  • I have said that you see the effect more dramatically, but it's also on film from a real baseball match in April this year was filming the natives for the first time that it's curving there on what?

  • So who was it who explained this effect?

  • You were the first person to explain how you can cause a baseball.

  • The swing in the opposite direction took an Aussie to show you how it's done.

  • Exactly.

  • Uh, well, why don't we wait?

  • Don't we play a bit of ball with?

  • But with that thing, I don't think you can swing that as much.

  • Yeah.

  • Let's give it a shot.

  • Really, Warren?

Can you fix that?

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B1 INT ball rough smooth cricket baseball swing

The Science of Curveballs

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    林宜悉 posted on 2020/03/28
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