Here’s a question taken from a well-used first-year undergraduate physics text:
Suppose you are standing on the center of a merry-go-round that is at rest. You are holding a spinning bicycle wheel over your head so that its rotation axis is pointing upward. The wheel is rotating counterclockwise when observed from above. Suppose you now grab the edge of the wheel with your hand, stopping it from spinning.What happens to the merry-go-round?
For this problem, neglect any air resistance or friction between the merry-go-round and its foundation.
Little wonder why people get turned-off physics and end up thinking that it is irrelevant to the real-world. I mean, when has anyone ever stood at the centre of a merry-go-round with a bicycle wheel above their head? All the merry-go-rounds I have seen have a pillar running through the centre making standing their impossible to start with. And you would look so stupid that I’d challenge anyone to go and do this in public.
There are numerous more practical examples of conservation of angular momentum out there in the real world.
Later today, I get filmed as part ofthe Kudos Awards, on the ‘science communication’ work that I do. Part of what I’ll be saying is that us scientists should be making our respective subjects accessible (unlike the physics problem above). There are many people who regard scientists as boffins in white coats (I hate that word ‘boffin’ – it implies someone utterly disconnected from society) and science of being of no relevance to everyday life. I can just imagine a ‘boffin’ standing on a merry-go-round with a bicycle wheel…We scientists have a duty to show everyone just how much they rely on science for normal day-to-day activities, and that scientists themselves are not boffins but major contributers to everyone’s quality of life.