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Questions: Would a spinning torus lose its weight? Would a solid torus, spinning at 7,81 km/s radial speed completely loose it's weight on Earth-like object? Would it 'fly away' at higher speeds? {Everywhere bellow torus lay flat on surface of Earth and spins around vertical axe through its center}

Thoughts: I think it should as we live in bent space at you should apply force to anything that moves faster than escape velocity to keep it on Earth.

Characteristics of our bent space are: 7,81 km/s - first cosmic speed and 9.8 m/c^2 is gravitational acceleration of our planet.

This means than in 7,81km our planet curves by 9,8m. Meaning that if body will travel that distance faster it will end up higher, relative to surface and you should apply force to keep it same height at start point. This force will be aligned with gravitational pull and compensate for it (opposite direction).

Take bent space there should be 3 forces in rotating torus accounted for: 1. Gravitational pull, constantly pulling every part of torus 2. Rotational pull. Compensated by torus’s material strength 3. Apparent force due to curved space and high speed (well could be that forces 1 and 3 are same force – according to Einstein)

In my thought experiment I ignoring other forces, such as Earth spin, rotation around Sun and Moon rotation. Also I presume torus made out of material impossible to break. But hey, it is just hypothetically.

Conclusion: If mentioned above is true and spinning object will tend to fly away from gravitational pull of other body than it is possible to make ‘gravitational propeller’ for small objects like asteroids and tag them to other orbits. The possibilities are huge.

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  • $\begingroup$ Are you asking if a rapidly spinning torus will levitate? $\endgroup$ – PM 2Ring May 12 '18 at 20:00
  • $\begingroup$ No, you need 7,81 km/s radial speed (in the "up" direction) of the center of mass of an object for it to escape earths gravity. What makes you think a torus specifically can do what other spinning objects can't? $\endgroup$ – ja72 May 12 '18 at 23:36
  • $\begingroup$ No, you do not have to be in 'up' direction - near orbit satellites $\endgroup$ – Yuriy Panchenko May 13 '18 at 1:29
  • $\begingroup$ No, you do not have to be in 'up' direction - near orbit satellites moving parallel to surface and yet remain stationary relative to ground as if they fall over horizon. The thing is if you travel at 7,81 km/s you should always be at the same height - hence 'weight loss' as nothing pushes down and rather remain 'hanging in the air'. With faster speed weight will tend to be higher than previous point and it will have 'negative' weight. If every part of torus span to 7.81 km/s (say with radius 10km) will try to be higher than before - would not whole thing tend to lose its weight? $\endgroup$ – Yuriy Panchenko May 13 '18 at 1:38
  • $\begingroup$ Think about - "you need 7,81 km/s radial speed (in the "up" direction) of the center of mass of an object for it to escape earths gravity" - if, hypothetically, you traveling at 5 m/s slow speed from the Earth sooner or later you'll end up far from Earth's gravity without have to go 7.81 km/s. This 7.81 speed means traveling at near Earth's surface you wont fall on it. Lower speed - you'll fall and faster - you'll fly away from it (and actually you will apply some force to stay on Earth) $\endgroup$ – Yuriy Panchenko May 13 '18 at 1:47

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