posted by Billiez on .
Question related to a bicycle dynamo and a wheel.
Why a current flows through the bicycle lamp when the wheel of the bicycle turns?
The wheel turns a generator that produces a voltage. The voltahe lights uop the bulb.
Generator-run bike headlights are less commonly used these days. The higher efficiency of LED headlamps with alkaline or lithium ion batteries makes them a better choice; the lamps are smaller, and need no generator. I have not had to replace my LED light batteries for two years. The wheel drag resistance due to the generator also slows down the bike a lot. It is like pedaling with the brakes on.