Why doesn t the spinning top fall off?

It is directly related to the law of inertia in nature.

Each point on the top rotates in a circle in a plane perpendicular to the axis of rotation. According to the law of inertia, each point tries to move it away from the circumference at any given time. But all tangents are on the same plane as the circumference itself.

Therefore, every point in motion tries to keep it in the plane perpendicular to the axis of rotation. It can be seen that all the planes perpendicular to the axis of rotation on the top are also trying to maintain their position in space. That is to say, the axis of rotation itself, which is perpendicular to all these planes, is trying to maintain its orientation.

Therefore, the spinning top will not fall when it turns.

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.

Take out a spinning top, spin it on the ground, and start whipping it hard, as the top spins faster and faster.

The spinning top is also like a tumbler, although it only has a pointed touch, it sways from side to side and refuses to fall. That's the gyroscope effect.

Should: A rotating object has the inertia to maintain its direction of rotation (the direction of the axis of rotation).

The spinning top has only one direction of rotation and is already stable.

The principle of gyroscopic rotation is that one side of the gyroscope "rotates" around its own axis, and the other side "precessions" around the vertical axis.

The inertial ellipsoid of the rigid body relative to the fulcrum is called the ellipsoid, and the moment of inertia of the rigid body relative to the axis of symmetry is called the polar moment of inertia. The moment of inertia of a rigid body relative to the other two principal axes passing through the fulcrum (see moment of inertia) is called the equatorial moment of inertia. A gyroscope is a rigid body that moves around a fulcrum, so the kinematics and dynamics equations for fixed-point motion of a rigid body are applicable to gyroscopes.

The history of the spinning top.

More than 1,700 years ago, during the Jin Dynasty, another interesting toy appeared in China - bamboo dragonflies. After this toy was introduced to Europe in the 18th century, it was called "China's top product" by Westerners. In this way, any rotating body can be seen as a spinning top.

Like the empty bamboo we play, acrobatic turntables, plate beating, hat throwing, and ballet spinning all use the principle of spinning tops. In the world around us, spinning tops can be found everywhere. From atoms to the earth, it can be seen as a spinning spiral.

The above content reference: Encyclopedia - Gyroscope.

Gyroscope properties – axial fixability.

The spinning top does not fall over during rotation, thanks to the first property of the spinning top, which is called axialization. When the gyroscope is rotating, if the moment of the external force acting on it is zero, it can be seen from the angular momentum theorem that the angular momentum of the gyroscope for the fulcrum is conserved, and the direction of the angular momentum remains unchanged in motion. Each point on the top rotates in a circle in a plane perpendicular to the axis of rotation.

According to the law of inertia, every point tries to move itself away from the circumference at any time along a tangent of the circumference, but all the tangents are in the same plane as the circumference itself. Therefore, each point tries to keep itself in the plane perpendicular to the axis of rotation when it is in motion. The conservation of angular momentum is seen everywhere in life.

When a figure skater folds her hands or hugs her chest, the distance from a part of her body to the spindle decreases, the angular velocity of rotation increases, and the athlete spun rapidly.

Gyroscope characteristics – precession.

The second property of a gyroscope is precession. When the gyroscope rotates at high speed, the central axis of the gyroscope seems to be rotating around an erected pole, and the phenomenon of rotating the axis of the object at high speed in space is called precession. This is because when the gyroscope is subjected to the moment of gravity on the fulcrum, according to the angular momentum theorem, the vector direction of the angular momentum follows the rotation of the gyroscope, tracing a cone.

In fact, due to the tidal forces exerted by the sun and the moon, our earth has been constantly and slowly precession, and the long-term precession is called precession. In our daily life, we can often see precession, for example, when the bicycle is moving, if it is slightly skewed, as long as the front of the bike is slightly turned in the other direction, the car will be balanced. It is gravity that creates a braking torque on the tire fulcrum, which causes the car to return to balance.

The characteristics of the gyroscope - nutation.

The third characteristic of a spinning top is nutation. It is impossible for the top to spin endlessly, and when the top starts to fall slowly due to friction, the motion done is nutation. Nutation refers to the change in inclination of the angular momentum around the axis of rotation between two angles when a rigid body is precession, and the Latin word means nodding.

While the top is precession, the top of the top is still making a "nodding" motion.

nutation is a very common movement in celestial bodies, and nutation also exists on the earth, and it takes years for the earth to "nod once". The ancient calendar of our country refers to the 19th year as a chapter, so this movement is called nutation.

1.Tie the mulberry bark to the tail of the stick.

2.Then wrap the mulberry bark in a clockwise direction nearly 1 cm from the head of the top.

3.Place the top on the flat ground, press the head of the top with your left hand to prevent it from falling, hold the head of the stick with your right hand and pull it hard, and the top will start to spin.

4.When you start turning, you have to swing the stick to drive the mulberry bark to beat the waist of the top parallel to the direction of the top (with a little more force), and the top will be stable.

You wrap the top with a whip, and the whip throws it out and spins up.

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.