Comments by "Ludmila Ivanova" (@ludmilaivanova1603) on "Veritasium" channel.

  1. it would be better explained if we think about the centre of the small circle and its travelling distance which will be 2pi (R+r). At the same time, the point on the small circumference travels 2pir distnance. The ratio of the two gives us the number of revolutions.
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