Is it possible to pump a swing 360 degrees?

AI Thread Summary
It is possible to pump a swing to achieve a complete 360-degree rotation, especially when the swing is connected by a rigid rod instead of a rope or chain. The ability to manipulate rotational inertia by adjusting body position, such as standing or crouching, plays a crucial role in this process. Performers in circuses have demonstrated this technique using shorter swings, which contribute to a smaller moment of inertia. The discussion highlights the importance of angular momentum in achieving the full rotation. Overall, with the right conditions and techniques, completing a full swing rotation is feasible.
rlaworms
Messages
2
Reaction score
0
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.
 
Physics news on Phys.org


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...
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...

Similar threads

Replies
1
Views
912
Replies
5
Views
2K
Replies
6
Views
7K
Replies
2
Views
2K
Replies
8
Views
5K
Replies
4
Views
4K
Replies
6
Views
6K
Back
Top