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why does a spinning top not fall over
Stand a top on its tip and it topples in a blink. Give it a hard spin and it stays up. Same top, same gravity. What changed?
It is not magic and gravity is not weaker. The top touches the floor at one tip, and gravity tugs on its middle, off to the side of that tip.
Spin first. A spinning top has angular momentum, called L, a vector that points along its axle. The faster the spin, the bigger it is.
Now gravity, pulling down on the middle. Off to one side of the tip, it makes a torque, and that torque points sideways, not down.
Torque changes angular momentum: the change in L points along the torque. Torque is sideways, so L's tip slides sideways, around a circle. That is precession.
How fast does it circle? The precession rate is m g r divided by L. A bigger spin means bigger L, so a slower, steadier wobble.
Here is why it finally falls. Friction at the tip steals spin, L shrinks, and the circling speeds up until the wobble throws it over.
A spinning top is never defying gravity: its spin turns the push sideways, until friction slowly takes the spin away.