Why does the spinning top spin at high speed not fall, but rotate more steadily?

When a mechanical system (object) is acted upon by a number of forces, if its net force (magnitude, direction) is zero, and the sum of the moments of each force at any point is also zero, the mechanical system is said to be in equilibrium. In other words, when an object presents a state of perpetual motion and static static, it can be called equilibrium. Objects are in equilibrium in many situations, not only when they are at rest, but also when they are moving (including the movement of stars), some of which are long-lasting, while others are only short-lived.

Generally speaking, static equilibrium is mostly stable equilibrium, while dynamic equilibrium is mostly unstable equilibrium. When the gyroscope rotates under force, the sum of centrifugal forces in all directions reaches equilibrium, so the gyroscope can temporarily stand with the shaft end to maintain the balance phenomenon, and then affected by various factors such as air resistance, ground friction, or the gyroscope center of gravity, the force of its rotation is gradually weakened, and when the rotating power disappears, the gyroscope also falls down with the left and right. Therefore, how to make a good spinning top, grasp the strength and mastery of the throwing top, so that the spinning top can be thrown more accurately and rotate longer, has become the ultimate goal of the gyroscope challenge.

You should think differently.

The physicist took out a spinning top, spun it on the ground, and began to whip it vigorously, and as the top spun faster and faster, the top swayed from side to side and refused to fall, even though it only had a pointed touch. This is known as the gyroscopic effect: a rotating object has the inertia to maintain the direction of its rotation (the direction of the axis of rotation).

The experiment of the gyroscope tells us that the high-speed rotating thing has a property, that is, it can keep the direction of the axis unchanged, and the stubbornness of the gyroscope is called the stability of the gyro. The spinning top always keeps its axis upwards after turning, and although its feet are very sharp, it does not fall.

Because the center of gravity of an object rotating at high speed will decrease.

The main reason is that momentum moment is balanced. Momentum moment is a basic concept in rigid body mechanics, and its magnitude is determined by the moment of inertia of the object, the angular velocity of rotation.

When the gyro rotates, the direction of his momentum moment is vertical, because he is not subject to the moment in the direction of rotation, so the momentum moment is balanced.

This is because when the gyro rotates, it is balanced by the centripetal force.

Analysis: Since a rotating object has the property of keeping the direction of the axis constant, the faster it rotates, the less likely it is to change the direction of the axis, just like a gyroscope. If the top doesn't turn, it will tip because there is only one fulcrum under the tip of the stationary top, and because gravity has a strong moment on this fulcrum, the top will fall downward around this fulcrum.

If an external force is applied to the gyroscope to make the gyroscope rotate rapidly, the gyroscope will not fall down, and the high-speed rotating gyroscope can keep the direction of the axis unchanged, which is the stability of the gyroscope.

Summary. Hello, dear, I'm glad to answer for you: why the top spins fast but doesn't look fast is related to the strength and speed of the whip, as well as the amount of friction on the ground.

This may be a matter of angle, because from different angles, you may see different things, as the saying goes, when you look at the side of the ridge as a peak, the distance and the height are different, which shows that different things are different from different angles, so this is basically the same as the fan spinning fast, but it seems to be slow.

Hello, dear, I'm glad to answer for you: the top spins very fast, but it seems that the number of rounds is not fast, why is it related to the strength and speed of the whipping, as well as the friction of the ground. This may be a matter of angle, because from different angles, you may see things differently, as the saying goes, the horizontal view is the peak on the side of the ridge, and the distance and distance are different, which shows that different things are different from different angles, so this is the same as the fan spins fast, but it looks like the reason is basically the same.

Due to the phenomenon of visual persistence of the human eye, the human eye cannot see each frame of rotation continuously. Our brain then completes the intermediate process based on the frames our eyes see. But when the speed of rotation is too high, the result of our brain nucleus setting sail will be different from what actually happens, and we will see that we are turning at a very slow speed, or even reversing.

Hehe, I'm learning spinning tops. Let's put it this way, your description is exactly one of the gyroscope errors, which is one aspect of the gyroscope's manufacturing error. It can be said that modern machining technology has made this error very, very small.

In fact, the ideal high-speed rotating gyroscope has good axis fixation, because the angular momentum of the gyroscope becomes very large due to high-speed rotation, and the influence on the gyroscope becomes very small when the external moment is disturbed. To use a very inappropriate analogy, a truck running at high speed has a lot of momentum, and relying on the friction of the ground alone, without braking, you will see that the truck can continue to walk far, far after the engine is turned off. This is because the frictional force is small relative to the momentum possessed by the truck and has no significant effect on the motion of the car.

That's why when we're riding a bike, when we're fast, the bike will go a long way even if we don't pedal hard.

Similarly, when the gyroscope rotates at high speed, the frictional moment and other interference moments, including the manufacturing error you mentioned, are relatively small relative to the angular momentum of the gyroscope, and the impact is small, so it has good axial fixability.

In fact, the higher the rotational speed, the better the axiality because the angular momentum is large. This is also the reason why we see that the gyroscope has a very small speed and will fall, at this time, a small frictional moment will change its angular momentum, making its motion change dramatically.

I wish I had made it clear enough.

First of all, you have been talking about asymmetry for a long time, and you are still talking about asymmetry. That is, your thing is definitely uneven, but in reality, the spinning top is not spinning according to the central axis you imagined. If it is not uniform, there is no axis of symmetry, and the rotation of the gyroscope in practice is not a fixed axis rotation as ideal, but a more complex movement.

And even if it is an ideal gyroscope, due to the different initial conditions, such as tilting, the movement is also different, and it is generally decomposed into the superposition of precession and nutation to deal with, not a simple centripetal force. Specifically, you need to learn theoretical mechanics.

As for the reason for stability, roughly speaking, after the gyroscope rotates, once there is an inclination angle, the moment of inertia in the horizontal direction will only change direction in the horizontal plane under the action of gravitational moment, causing the gyroscope to precession, but not to cause the gyroscope to fall. If you can't understand this, in other words, once an object falls over a certain angle, gravity will cause it to fall more and more, and eventually fall. If the top turns and falls, gravity will only make it spin in the horizontal plane and not continue to fall, so it is very stable.

If you don't understand it, you will know that the result is okay.

Gyroscopic stabilization is due to the moment of inertia, the faster it rotates, the greater the moment of inertia and the more stable it is.