WHY DOES A CRICKET BALL SWING ? - REVERSE SWING EXPLAINED

In this video, we break down the physics behind swing bowling. We talk about the main cause of swing bowling- asymmetrical boundary layer separation. Conventional swing (in swing and out swing) happens in new shiny balls where the boundary layer is tripped by the seams while reverse swing occurs when the ball is relatively old and the roughness causes asymmetrical boundary layer separation. This asymmetry leads to a force imbalance on either side of the ball which gives rise to swing.
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[@Soumil-f7]

Very nice video...out of curiosity, I didn't fully understand the reverse swing part....In the diagram when you label the "Force", what kind of force do you exactly mean , is it gravity?

[@flamingfrancis]

Great in theory but there is not one mention of the reason a ball swings...difference in Coefficient of Friction between the two surfaces. Why also, does the Rules of Cricket allow bowlers to shine / polish the ball on their clothing. Why is this allowable when doing the opposite, roughing the surface, is illegal. It shows up the mindlessness of rule making. ANYTHING that is done to alter the natural condition of the ball should be outlawed.

[@sheldoncooper3373]

You are talking about reverse swing. Where the videos is talking about both new ball swing and reverse swing.
Polishing the ball is legal in this sense it is the natural property of the ball that it had a smooth surface once(before play).
So there is nothing wrong in trying to keep that shape.
Now to the 2nd part:
Swing is an important part of cricket. Even with this rule, still the game is batsman dominated. That's why to provide a balance this polishing thing is allowed.
Though now a days it doesnt even matter in odi game bcz of two new ball rule.

[@jayshinde9590]

In which direction does the ball swings, turbulent boundary layer or towards laminar boundary layer?

[@sumitvermacricketbowlingba5748]

ruclips.net/video/OH0u8yX9k08/видео.html

[@sheldoncooper3373]

Suppose an inswing for right hander, seam is towards the leg slip.
The laminar effect is happening on the left side of the axis, while the turbulence effect on the right side.
Isnt the laminar effect is causing the ball to move?
I mean in this case ball is bending towards right side ( inswing for right hander)...even though right side has turbulence effect ( and you said turbulence effect is more powerful)
Looks like the even though turbulence effect is more powerfull still the laminar effect is forcing the ball to swing as it is parallel to the skin of the ball and properly distributed while the turbulence effect is just making the air scattered and thats why the pressure is not working.

[@s.sweekar-2651]

But, isn't the laminar flow separation delayed by roughening the surface like in Golf balls?

[@shauryasuman9557]

he proudly said "we are the 2 broke scientists"

[@bloomingstarscricketacadem6461]

Why reverse swing need more pace

[@kuldeepsharma9752]

Pls clear more concept on reverse swing along with aerodynamics factors on swing

[@2BrokeScientists]

What aspects of reverse swing do you want us to cover? Let us know and we will try making another video.

[@lavsharma257]

Brother u make things much more easier than it is..hats off

[@ravinaveen8714]

Nice explanation

[@joebloggs4295]

Awesome guys

[@vedantgupta6734]

Simple yet brilliant explanation ! Great work 👍

[@2BrokeScientists]

Thanks Vedant!!

[@s.sweekar-2651]

Got it