# 226: Swingset

 Swingset Title text: Someone bring me a pocket fan so I can drift around the yard.

## Explanation

In the opening panel of this comic, Blondie, possibly as Miss Lenhart, sees Cueball sitting on a swing set. She tells him that during his swing, he becomes weightless. Cueball then imagines that at the peak of his swing he is able to become permanently weightless, floating above the ground without any support.

When on a swing or other pendulum ride, there is a moment between swinging forwards/backwards and swinging back down again when the forces of gravity, friction, air resistance, etc., bring the velocity of the swing to zero. At this moment, there is no acceleration toward the pivot of the swing (since the centripetal acceleration is proportional to the square of the speed). So the swinger experiences no centripetal force. Of course, gravity still acts on the person, but if the swing is horizontal at that point, then there is no reaction force, so for one moment, the swinger is in free-fall and experiences weightlessness. However, that weightlessness can only be maintained for a fraction of a second, so if Cueball tried this in real life, he would come crashing to the ground.

In the title text, Cueball asks for a pocket fan, believing he could fly around the yard using this small device perhaps as a propeller.

## Transcript

[Woman talking to Cueball on swing-set.]
Woman: You know, at the peak of a big swing, you become weightless.
[Thought bubble from Cueball.]
[Cueball swings higher and higher. At the peak of a big swing, he shoves himself off the swing. Cueball remains hovering in the air.]
Cueball: Hey guys. Come check this out.

# Discussion

A glass with water can be momentarily inverted at this moment and the water will not leave the glass!--DrMath 08:56, 16 November 2013 (UTC)

Isn't the point about illustrating that you do in fact have weight even in instences that are written off as weightless? In space you just happen to be falling at the same velocity of your surroundings, maintaining orbit simply by moving fast enough to miss the Earth. On top of which, in a low enough orbit g is still close to 9.8 m/s^2 if only because altitude is insignificant compared to the radius of the Earth.--Passing Stranger 14:10 August 2014 (UTC)

No, you don't have weight in some instances. Weight is dependent upon gravity, so in deep space with no planets or stars close enough to matter you would be weightless. Mass, on the other hand... 173.245.50.154 01:46, 10 January 2015 (UTC)
He was talking about orbit around a body, where in one sense you still have real weight. The bureaucrats on the ISS have nearly earth-normal weight, being only what, five percent farther from the center of the earth's mass? That weight is simply hidden by the fact that everything else around it has the same relative velocity, all of it falling at the earth and eternally missing, thanks to its forward velocity. I miss Douglas Adams. —Kazvorpal (talk) 01:48, 22 October 2019 (UTC)