Russian figure skater Kamila Valieva is the first woman to land a quad jump at the Winter Olympics. After seeing Valieva's performance, I knew I had to analyze her history-making jump, which was the first jump of her routine. Check out Valieva as she initiates her quad.
Valieva's right leg is bent with lots of stored energy while her left leg and right arm are extended so that she can pull them in fast, doing work to get herself spinning. In the next image, Valieva leaves the ice.
She's already spun half a turn. Her arms and legs are moving inward so as to reduce her moment of inertia and increase her spin rate. The image below shows Valieva after her first turn.
Isn't that wonderful! Valieva has moved her arms and legs as close to her spin axis as she can, minimizing her rotational inertia. Her skirt hasn't been thrown outward; it's horizonal so that tension in the fabric can provide the inward force necessary to keep the skirt moving in a circle. A great look at Valieva near maximum height is in the image below.
The image below shows the completed third turn.
Now it's time to return to the ice with a completed fourth turn, as the image below shows.
The guy on the left has a great look at history being made!
From the first image above to the last image, Valieva needed just 0.93 seconds. I estimate about a sixth of a second for Valieva's third turn, which leads to a rotational rate of about 360 rpm. That rotational rate is about 80% of the rotational rate for helicopter rotor blades! She jumped from the ice with a speed of about 7 mph and reached nearly 20 inches in height off the ice. That's a great jump!
