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  • How Does a Bicycle Stay Upright?

  • If you get on a bicycle and start pedalling, what do you feel?

  • You will feel the movement of the bicycle, as you move forward.

  • Doesn't it fill you with surprise that you can move forward on two wheels, just by pedalling

  • your way?

  • Let's see what happens when a stationary bicycle is pushed without a rider.

  • Oh, look!

  • The pushed bicycle keeps moving.

  • It's becoming slower and now it has fallen!

  • Oh!

  • No!

  • A moving bicycle will continue to stay upright and move forward because of momentum, till

  • it falls down because of gravity.

  • Did you know that till a few decades back, scientists thought a bicycle stays upright

  • because of the Gyroscopic Effect.

  • The Gyroscopic Effect means that a spinning wheel tends to stay aligned in its original

  • direction, during momentum.

  • This is known as Angular Momentum or spinning action.

  • So, if it is not the Gyroscopic Effect, what actually keeps the bicycle upright?

  • The scientists who study bicycles, experimented a bit more to discover, that if the gyroscopic

  • effect were to be cancelled, the bicycle would continue to be upright!

  • So, they assumed, it must be the caster effect of the wheels.

  • Because the bicycle wheels are attached to a centre axis on a frame to help them rotate.

  • What is the caster effect's role in keeping bicycles upright?

  • If you look at a bicycle, you will see that it is designed in such a way, that the front

  • wheel's steering axis makes the front wheel move faster than the back wheel.

  • So, when the bicycle starts moving to the left, the Centrifugal Force of the back wheel

  • would keep it in check, because it is still moving straight.

  • The wheel would automatically snap the bike to the right and keep it upright!

  • So, now you know, that Angular Momentum and Centrifugal Force keeps a bicycle upright

  • when it is moving.

How Does a Bicycle Stay Upright?

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