How the small dynamo in a bicycle works

The video tutorial explains how small dynamos generate electricity using a bicycle. It describes the construction of a small dynamo, involving a cylinder, a U-shaped magnet, and a coil. The demonstration shows how the movement of the bicycle wheel generates electricity, lighting a lamp. The video also compares small dynamos to large ones used in cities, highlighting the differences in their construction and application.

What new insight or understanding did you gain from this video?