Pitara Kids Network

Why does a Cricket Ball Swing?

How many times have all of us heard that the former captain of the Indian cricket team, Kapil Dev, was one of the greatest out-swing bowlers of all times. Indeed! He took more than 430 wickets in Test cricket. But, do you know how a cricket ball swings?

The term ‘swing’ refers to the movement of the cricket ball in the air after it leaves the bowler’s hand, which takes the ball away from or towards the batsman. If the ball moves away from the batsman it is called an out-swinger; if the ball moves towards the batsman it is called the in-swinger.

A Swing in the Tale [Illustration by Shinod]

On to the seam
The cricket ball swings because of its shape and shine. If you look at a cricket ball carefully, you will see a narrow strip at the centre, which is considerably raised. This is called the seam. Actually, a cricket ball is made of two pieces of leather, which are stitched together along the seam.

Seam + shine + wind = swing
Have you ever noticed that bowlers keep rubbing and polishing one side of the ball? This is done to maintain the shine of the ball on one side and keep the other side rough. This is the key to the swing of the ball.

The side that has the shine provides little resistance to the wind, while the rough side resists the flow of the wind. The fast moving wind on the shiny side hits the raised seam and pushes the ball in the opposite direction, thus making the ball swing.

Out-swingers and in-swingers
If the shining side is kept on the left hand side while bowling to a right handed batsmen, you will get an In-swinger as the wind will push the ball into the batsmen. Similarly to get an Out-swinger, a bowler keeps the shining side on the right side while delivering.

A twist in the tale: the reverse swing
From time to time we have heard it being said that a particular cricketer can make the ball reverse swing? Whatever does that mean?

The reverse swing is a method through which a ball can be made to be swing in the opposite direction. That is, with the action of an out-swinger you can achieve an in-swinger. But how is this possible, you would ask?

Yes, this is where controversy steps in. Reverse swing can be achieved by tampering with the ball, i.e. raising the seam forcefully, or damaging the bowl intentionally so as to make the shining side heavier than the rough side. Ball tampering or damaging is not permitted by international cricketing rules and bowlers can be suspended for doing it.

So the next time someone asks you about how a cricket ball swings, you’re sure to know the answer.