why and how do gears on a bike work? Why does it give more / less resistance for going up and down hills?

Question

why and how do gears on a bike work? Why does it give more / less resistance for going up and down hills?

In: 1

Answer 1

it changes how many far the wheel turn (how far you move) for each turn of the pedals

it is easier to turn the pedals in a low gear but slower, just like it easier but slower to move ten 10kg weigths than it is to move one 100kg weight