precession is a disgusting phenomenon of angular momentum
Let’s consider the ball:
At first, the top should spin vertically at “very high speed”, causing pain. The human brain, imagining this event, wants the top to collapse where it is like wood, but instead of piling up, the top will make a circular motion around its vertical axis. Here the error of the brain accustomed to Newton’s equation f = m * a is to ignore the fact of angular momentum; It would be better for him to think, rather than f = ma, that “the force f exerted by gravity on the center of gravity of the top will create a pair of magnitude f * r (r, arm of force) perpendicular to the plane formed by the angular momentum vector and by the vector f. It is simply: since this pair is perpendicular to the angular momentum vector, instead of decreasing, increasing or pulling it more horizontally (the top of the ball is stacked), it makes it draw a circle, causing the angular momentum vector to move in the direction of torque, as the physicist says (now, horizontally, for example) The torque created by the horizontal force that is applied to further rotate a disk that can rotate in the plane is in the same direction as the angular momentum vector, hence the applied torque makes the disk rotate faster, in other words, the angular momentum of the excrement increases, and we can understand this well from our experience with the earth, but not the preceding sion.)
Of course, these explanations are very approximate for very high angular velocities, when the angular velocity decreases, “nutation” comes into play, which is more a sinusoidal motion of “nodding” than the rotation of the top around the a and y-axis. .
there is also a photograph of niels bohr and another famous physicist bent over to watch the spinning top, telling us that things are not so child’s play … (top)
Wolfgang Pauli and Niels Bohr
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so we understand the phenomenon of precession through the example of the peak, but the question in my mind is: was Newton aware of the phenomenon of angular momentum? Oy Oy was certainly aware of being able to calculate planetary motions (perhaps it was Newton who defined the angular momentum, who knows). if so, they did not say “Oh, be careful if there is angular momentum”, when we have been shown cases where Newton’s second law f = m * a doesn’t work; so it is wrong to expect everything from the teacher 🙂 However, now they did not say: “Oh, be careful if there is an angular momentum, but if you are choosing a non-inertial frame of reference, they said that you cannot apply the value of Newton read as if you were in an inertial frame of reference “then I won’t believe it and yes the top is a non-inertial frame is the frame of reference (just like the earth), but one way or another (see inertial) , (see non-inertial), (see reference system), (see Newton’s laws), (see acceleration).
physics is not beautiful …
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