Pairs figure skaters

One discipline within figure skating involves a pair of skaters, one male and one female. The most spectacular move is a "throw jump", in which the male skater throws the female into the air so that she spins several times before landing on a single blade. The top pairs in the world (such as Zhang Dan and Zhang Hao of China, shown below) can send the female skater a horizontal distance L = 7 meters across the ice, and raise her center of mass h = 1.2 meters high.

It helps to have a big, strong fellow and a petite partner. Zhang Hao, for example, is about 5' 11" tall and weighs 159 pounds, while Zhang Dan is only about 5' 4" and weighs only 106 pounds.

1. How long is the female skater in the air?
2. What is her initial velocity (speed and direction)?
3. What is her maximum gravitational potential energy above the ice?
4. What is her maximum kinetic energy?

For more information

• Go to 4:25 on this video to see Dan Zhang and Hao Zhang perform a throw in slow motion.
• Another Zhang/Zhang throw triple this time from the short program at the 2009 Worlds.

Copyright © Michael Richmond. This work is licensed under a Creative Commons License.