Its always interesting for the cricket lovers to know whats the actual science behind the swing of ball specially reverse swing. Mostly players get the swing skills by practice but if they know what the actual science behind it they can enhance these skills and bowl according to weather and air conditions can create a lot of impact.
The all science behind in/out swing is Bernoulli’s Eauation which is give below.
where P and V are pressure and velocities respectively and they are inversely proportional to each other according to the equation. Higher the velocity lesser will be the pressure to keep left side equal to constant and vice versa, keep in mind that the ball always deflect towards the low pressure. Bowlers keep the ball one side shiny and the other side rough . When bowler bowls the ball and ball follow its trajectory air move less obstructly from shiny side compare to rough side, air velocity will be higher on rought side means pressure will be low and ball deflect towards it called swing. Reverse the sides for opposite swing.
Reverse swing mostly concerned with the oldness of ball and its heavier and lighter side. If ball is not heavier at one side reverse swing is not possible. But after getting required ball features for reverse swing it still requires a lot of practice and acurate arm angle to reverse swing the ball. That is the reason bowlers scratch the ball at one side to get the reverese swing called ball tempering which is against ICC rules and bowlers who focused on reverse swing got arm injury occasionally.
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