2007-01-29 04:34:59 · 3 answers · asked by Viswanathan M 1 in Science & Mathematics ➔ Physics
The short answer is "conservation of angular momentum". If the top leaned towards any one side, the turning produces a "torque" that pushes it back up.
2007-01-29 04:48:29 · answer #1 · answered by Kitiany 5 · 0⤊ 0⤋
The glib answer is conservation of angular momentum. But what does that mean?
Think of a point on the edge of the spinning top. At any moment it is whizzing along in a given direction with a given mass, so has some momentum.
Making it change direction requires a force, because it means accelerating the point. Thats OK for the circular motion, because it is attached to the axis of rotation, and so the force is provided by the material of the top itself.
But what if you want to let the top fall over? This also involves an acceleration (this time down or up) and so requires a force. Add this up around the whole rim of the top and a force is needed to push it off axis in any direction.
If the top is spinning fast enough, gravity is not enough to provide this force even if the top is a tiny bit off axis.
2007-01-29 12:51:16 · answer #2 · answered by Anonymous · 0⤊ 0⤋
It's center of gravity is in motion and thereby stable according to the laws of centrifical force and simple inertia
2007-01-29 12:45:06 · answer #3 · answered by photogbob2003 2 · 0⤊ 0⤋