India scored a thumping win against Pakistan at the ICC Men’s ODI World Cup match in Ahmedabad on October 14, with the latter’s batters folding for 191 following a collapse at the start of which they were at a healthy 155/2. Five of India’s six bowlers took two wickets apiece in the rout, although they were led by Jasprit Bumrah and Kuldeep Yadav, who induced the collapse with the wickets of Mohammad Rizwan and Iftikhar Ahmed, respectively.
But for all the magic on display, Bumrah’s delivery to dismiss Rizwan in the last ball of the 34th over stands out for illustrating an everyday occurrence in cricket but at a magnitude commonly seen in physics textbooks and high-school laboratories, less so on the cricket field. The delivery was a slow offbreak – a ball delivered at 122 km/hr that, after bouncing, jagged sharply into the right-handed batter. There, a gap between bat and pad, which Bumrah had spent the first five balls of the over opening, allowed the ball to hit the stumps.
While slow offbreaks aren’t exotic in cricket, the one that Bumrah bowled was. After pitching, the ball’s kinetic energy through the air dropped noticeably, so much so that it reached Rizwan much slower than at 122 km/hr. The law of conservation of energy can’t be violated, so where did the ‘missing’ speed energy go?
