Is this possible for hanging objects from spinning sphere?

In summary, the conversation is about a spinning sphere ride with objects hanging from strings. The speaker believes this ride is theoretically impossible because the objects on the top hemisphere cannot stick straight up without external forces. Their friend disagrees and thinks the objects can stick out with the strings perpendicular to the surface of the sphere if it spins fast enough. However, the speaker still believes that even with infinitely strong strings and a fast-spinning sphere, the strings would still be perpendicular to the ground. They also discuss the use of fixed beams instead of strings and the need for rigid tethers and mechanical control for the ride to work. They also acknowledge that the video is not real, but still find it entertaining.
  • #1
hellohello
1
0
This youtube clip has a ride that is a spinning sphere with objects hanging by strings from the surface.

(see at about 0:55)

This is the only ride in the video I think is theoretically impossible (the others seem like they could be done but would be dangerous and/or costly). I think it's theoretically impossible because there is no way objects on the top hemisphere could stick straight up, with their strings perpendicular to the surface of the sphere, without some external force like wind blowing from the ground up. If you deconstruct the sphere, which is only spinning along the z-axis in the theta direction, it is like many thin rings stacked on top of each other. If you take anyone of those rings with an object hanging from it and spin the ring (only in the theta direction), the highest up off the ground it could be is (just short of) the height of ring from the ground, with only natural forces acting on it.

My friend thinks that these objects could be sticking out with the strings perpendicular to the surface of the sphere no matter where they are on the sphere, except at the very top, if the sphere is spinning fast enough.

I think that even if the strings were infinitely strong and the sphere were spinning infinitely fast, the strings that the objects were hanging from would be perpendicular to the ground (not the surface of the sphere).

Am I right?
 
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  • #2
hellohello said:
Am I right?
Yes, everything is correct.

You could use fixed beams instead of strings for the upper sections to get seat positions above the topmost part of the sphere.
 
  • #3
You realize that nothing in that video is real right?
 
  • #4
You are correct. Your friend is wrong.

If those tethers are not rigid, the highest that any particular pod could go is with its tether parallel to the ground.

The only way the idea could be realized is to make the tethers rigid AND to mechanically control the angle at which they emerge from the sphere.
 
  • #5
mrspeedybob said:
You realize that nothing in that video is real right?
It's still hilarious: Gravity is an error.
 
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  • #6
A.T. said:
It's still hilarious:

I agree.
 

1. Can objects be hung from a spinning sphere without falling off?

Yes, it is possible to hang objects from a spinning sphere without them falling off. This phenomenon is known as centripetal force, which is the force that acts on an object moving in a circular path and keeps it from flying off in a straight line.

2. What factors affect the stability of hanging objects on a spinning sphere?

The stability of hanging objects on a spinning sphere is affected by the speed of rotation, the weight and shape of the objects, and the strength of the string or support used to hang them. The faster the sphere spins, the more stable the objects will be. Objects with a lower center of mass and a streamlined shape will also be more stable.

3. How does the direction of rotation affect the hanging objects on a spinning sphere?

The direction of rotation does not have a significant impact on the stability of hanging objects on a spinning sphere. As long as the sphere is spinning at a constant speed, the objects will experience the same centripetal force regardless of the direction of rotation.

4. Is it possible to hang multiple objects of different weights on a spinning sphere?

Yes, it is possible to hang multiple objects of different weights on a spinning sphere. As long as the objects are hung at different distances from the center of the sphere, they will experience different amounts of centripetal force and can remain stable.

5. What is the maximum weight that can be hung on a spinning sphere without falling off?

The maximum weight that can be hung on a spinning sphere without falling off depends on several factors, including the speed of rotation, the strength of the string or support, and the shape and weight distribution of the objects. In general, the heavier the objects and the faster the sphere spins, the stronger the string or support will need to be to prevent them from falling off.

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