While most of us enjoy the head rush of oscillating on a playground swing, for Dr Arnab Bhattacharya swings are “examples of the principle of energy conservation”.
For the Tata Institute of Fundamental Research (TIFR) scientist, slides are tools to “enjoy gravity safely” and merry-go-rounds are illustrations of that “very mysterious thing” called centripetal force.
In the first of this month’s ‘Chai and Why?’ series at the Prithvi Theatre, Bhattacharya spoke to a young audience about science in the playground.
Despite his early disclaimer that he was pathetic at classical mechanics, which incorporates playground science, his talk and live experiments had the audience bursting with questions and ideas.
Not satisfied with a single experiment, which used a ramp to show the effect of an object’s weight on its speed and acceleration, the audience demanded an encore. “Use the bigger sphere,” they commanded. “Change the angle of the slide. Switch that ball for a ring. Try the same thing with a cuboid…”
“Kids are all intrepid researchers,” said Bhattacharya. “They want to probe the world around them. They learn things from experience that researchers still can’t adequately explain.”
To involve the crowd, he asked a girl from the audience to explain how she used a swing. She shyly explained how she sat on the swing, then leaned forward and backward to speed up. Everyone giggled when Bhattacharya used a series of complicated equations to explain the concept so simply put forward by the girl.
“Scientists publish papers on swings, and (create) computer simulations too,” he said.
The audience enjoyed the lecture-cum-demonstration.
Madhuri Menon, who had come with her 12-year old son Arjun, said: “I’m an engineer, and Arjun likes science, so I wanted him to see science in real life, not just plain facts.”
Adults and children gasped and applauded while watching a video of Estonian Kiiking athletes performing heart-stopping stunts on modified swings, which also raised puzzled questions on unstable equilibrium.