Weightlessness

It is interesting, whether there is weightlessness in objects in the fall, i.e., while they are flying down, of course, without taking into account air resistance. Weighing gives a zero result - nothing weighs, neither light nor heavy. And if there is no weight - hence, weightlessness? Is it so easy to get weightless even on Earth?

It is interesting, whether there is weightlessness in objects in the fall, i.e., while they are flying down, of course, without taking into account air resistance

Let's ask: what is weight? This is the force with which the body presses against the support - the scales, the floor, etc. There is no support - there is no weight!

If you shoot a cannon from a mountain, as described by the great Newton, then the core of the cannon would fly with increasing speed, and so it would fall on Earth farther and farther from the gun, while at the first cosmic speed 8 km/s did not start to fly around the globe in a circle and would become a companion of the Earth. In all these cases, the core would experience weightlessness, since it fell, not relying on anything. And starting to rotate around the Earth, this weightlessness would have been preserved for the entire time of the flight of the nucleus. Does this mean that the core is not attracted by the Earth? No, gravity acts on it, but there is no support, and the core moves with acceleration. But the core does not pressure anything, and therefore does not weigh.

In the novel From the Gun to the Moon, Jules Verne also assumed weightlessness, but only when the core with the passengers, released from the huge gun to the Moon, reached the point at which the attraction of the Earth and the Moon was the same. But then Jules Verne was wrong - this weightlessness should have occurred immediately after overcoming the core of earthly atmosphere.

Often weightlessness is compared with the swimming of bodies, when their gravity is compensated by the buoyancy of water. This is not the same thing at all. The pushing forces act on the surface of the body, but everything that is inside has weight. Do not fly the same sailors inside the submarine, like astronauts. At the same time, the whole submarine in the water is balanced and, therefore, undergoes weightlessness.

A diver who is in the water, too, "has no weight" in it, but also his heart, and stomach, and brains continue to weigh their and put pressure on the appropriate places of the diver.

You can create a "weightlessness" in an airplane, for example, diving down, and even with a certain thrust of engines that compensates for air resistance. Such an aircraft falls with an acceleration of free fall - 9,81 m/s² and inside it almost total weightlessness. But at the end of the fall you have to make a turn to avoid bumping into the Earth. Here, the nature is recouped on the passengers by overloads!

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