Cycling

[Henryn]

Why is it easier to stay on a bicycle when it's moving?

[Peter R]

The easy answer - coz your moving. The real answer requires some hard thinking... The reason you dont usually fall off the bike is because you have to change your direction of movement to do so - from movement ahead to movement down :-). Physics says that to change direction requires energy, so it takes energy to get you to fall off. The faster you go, the more energy it takes to change direction (think of turning a corner in a car - its harder if youre going faster). So, falling off is just like turning a car - the faster you go, the harder it is!

[incitatus]

If you think about that answer it doesnt hold up either. You have no lateral velocity when riding a bike, so changing moton in that direction is no harder than when stood still. You could topple over in the roll direction easily either way. The answer is very complex. There are contributions from your own sense of balance, the centrifuge effect of the bike wheels, the rudder effect of your passage through the air, and many more.