# Physics Behind Figure Skating

## Jumps

The skater must combine speed, force, vertical velocity, momentum and perfect timing in order to successfully complete a figure skating jump.

## Angular Momentum

In order to obtain height and speed, the figure skater must utilize angular momentum. Angular momentum determines how fast a figure skater can rotate in a jump. More angular momentum means that the skater will have the potential to spin faster. A skater can obtain angular momentum by pushing off the ice with his/her foot.

## Vertical Velocity

By pushing off the ice with his/her foor he/she can gain vertical velocity. More vertical velocity allows a skater to travel higher into the air. Producing forces from the jump creates vertical velocity. When a skater contracts his/her muscles and extends his/her legs, he/she is pushing down on the ice, which causes the ice to create a force on the skater. This also creates vertical velocity. This follows the laws of projectile motion: The more vertical velocity the skater can produce, the higher the skater will jump.

## Arms Are Important

If a skater's arms are extended, the skater rotates slowly. If a skater's arms are close to his/her body, the skater rotates quickly. This follows the Law of Conservation of Angular Momentum. The smaller the body position, the faster the speed. The bigger the body position, the slower the speed. See the picture below to gain a better understanding of the Law of Conservation of Angular Momentum,

## Harder Than it Looks

If a skater can keep their body straight and keep their arms close to their body, they can obtain a very high rate of speed. However, this is not an easy task. Forces are trying to pull the body out to all directions. Most figure skaters cross their ankles in order to stay as straight as possible and keep their legs together.