"The wheel of laughter"

On the inertia in rotational motion the device of original entertainment is based - "the wheel of laughter", which can be seen, for example, in the parks. Visitors here have a chance on themselves to experience the action of inertia. The audience is placed on a round platform - standing, sitting, lying, - whoever wants. Hidden under the platform, the motor smoothly rotates it about the vertical axis, at first slowly, then faster, gradually increasing the speed. And then, under the action of inertia, all those on the platform begin to slide to its edges. At first this movement is barely noticeable, but as the "passengers" move away from the center and fall on the circle of an increasing and larger radius, the speed of movement is more and more noticeable. No effort to stay in place leads to anything, and the "wheel of laughter" dumps people.

The globe is, in essence, the same "wheel of laughter", only of gigantic proportions. Earth, of course, does not throw us off, but it still reduces our weight. And at the equator, where the rotation speed is greatest, the weight reduction from this cause, reaches a 1/300 fraction. And together with the other cause (the compression of the Earth), the weight of each body on the equator decreases, in general, by half a percentage point (i.e., by 1/200), so that an adult weighs about 300 g less on the equator than at the pole.

Inertia in the case of rotational motion except the "wheel of laughter" can be observed in the following experiment. Uncover the umbrella, put it end to the floor and rotate the handle; It will not be difficult for you to make him happy with the rapid movement. Now throw inside the umbrella a ball or crumpled paper; the abandoned object will not remain in the umbrella, but will be thrown out of it by what is commonly called "centrifugal force" and that in reality there is only a manifestation of inertia. The ball is thrown out not in the direction of the radius, but along the tangent to the path of circular motion.