Conservation of Angular Momentum
By Judy Evans
@JudyEv (371944)
Rockingham, Australia
February 16, 2026 7:13pm CST
I wonder how many will be tempted to skip this discussion given its fancy title! 
MyLotter LindaOh (@LindaOHio) was able to tell me how ice-skaters can increase their speed when swivelling on the one spot. I thought everyone might like to know a bit more about how it’s done. It’s a physics principle called ‘conservation of angular momentum’.
Firstly, ‘radius’ is the distance of the mass from the centre. If a skater pulls their arms and legs closer to their body, the radium is reduced and the spin becomes faster. There is no extra push which explains why I could never pick an extra push of any sort.
An example you can test for yourself is to spin an office chair while sitting in it. If you sit with your arms out, you’ll spin slowly but pull your arms in and the speed increases. To me, it’s almost like magic.
The photo was taken near Innsbruck, Austria.
MyLotter LindaOh (@LindaOHio) was able to tell me how ice-skaters can increase their speed when swivelling on the one spot. I thought everyone might like to know a bit more about how it’s done. It’s a physics principle called ‘conservation of angular momentum’.
Firstly, ‘radius’ is the distance of the mass from the centre. If a skater pulls their arms and legs closer to their body, the radium is reduced and the spin becomes faster. There is no extra push which explains why I could never pick an extra push of any sort.
An example you can test for yourself is to spin an office chair while sitting in it. If you sit with your arms out, you’ll spin slowly but pull your arms in and the speed increases. To me, it’s almost like magic.
The photo was taken near Innsbruck, Austria.10 people like this
10 responses
@akalinus (44357)
• United States
19h
@Ineeddentures I was not built for ice skating. My kids skated rings around me, so I saved the ice for them.
2 people like this
@snowy22315 (203066)
• United States
19h
The physics of it all is interesting to watch.
2 people like this
@DaddyEvil (168114)
• United States
20h
Yes, I know the principle but you said you wanted to talk to ice skaters and I'm not one so I didn't respond to your discussion.
That's a beautiful photo. 
2 people like this
@Ineeddentures (18008)
•
20h
Yep I used to spin faster with my arms in right enough.
I don't think I could spin at all now
2 people like this
@LindaOHio (214015)
• United States
1h
Thanks for the shout out. I still don't get how it works! lol
