Is it possible to pump a swing 360 degrees?

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rlaworms
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Is it possible to "pump" a swing 360 degrees?

Homework Statement


Is it possible to "pump" a swing so that it turns in a complete circle? Assume if you wish that the seat of the swing is connected to its support by rigid rod rather than a rope or chain.

Homework Equations


Angular momentum
Li=Lf

The Attempt at a Solution


We know that we can decrease or increase the rotational inertia by standing or crouching on the swing, respectively. However, we are not completely sure if those inertias alone will make it possible to swing in a complete circle.
 
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rlaworms said:

Homework Statement


Is it possible to "pump" a swing so that it turns in a complete circle? Assume if you wish that the seat of the swing is connected to its support by rigid rod rather than a rope or chain.

Homework Equations


Angular momentum
Li=Lf

The Attempt at a Solution


We know that we can decrease or increase the rotational inertia by standing or crouching on the swing, respectively. However, we are not completely sure if those inertias alone will make it possible to swing in a complete circle.

I have seen performers at a "humans only" circus [like cirque du soleil] do it!

Edit: They were using a reasonably "short" swing, much shorter than you see in a children's park, and did it in the standing position, so will have been working with a reasonably small moment of interia? and yes, rods not chains.
 


Oh, thanks. I kind of understand the question now.

So, it is possible to swing 360 degrees...