Acceleration is an important feature of all ice skating. The same as with motion, acceleration can be translational (in a straight line), or rotational (in a circle). If acceleration is rotational, then it is in an axial direction, pointing inward to the center of the circle of motion. This form of acceleration is called centripetal acceleration. Consider the following graph, excerpted from The Science of Ice Skating: Volume 3 from Schottenbauer Publishing. The graph shows acceleration during a figure skating spin.
Discussion Questions
Initially, which direction is vertical or nearly vertical?
At the end, which direction is vertical or nearly vertical?
Describe the relationship between the initial and final angles of the foot in relation to the floor.
Is it possible to identify how many revolutions are present? If so, how many? If not, why?
Is it possible to determine whether this is a slow or fast spin? If so, which is it?
What is the initial velocity? The final velocity?
What is most likely the cause of the spikes in the graph?
Additional free graphs are available in a free pamphlet from the publisher's webpage. The following books from Schottenbauer Publishing contain similar types of graphs and data pertaining to the science of ice skating, figure skating, and hockey:
What happens when an ice skater jumps? The answer can be modeled in various levels of difficulty. One the simplest level, assume that the skater is simply a point mass object, without movement within the body. In this analysis, acceleration occurs in three planes, leading to changes in altitude and rotation.
On the most complex level, the skater's body must be analysed as separate components moving in relation to the center of mass, which for most humans is approximately in the center of the abdomen or hips.
Discussion Questions
What everyday motions are related to skating?
If skater motion were to be studied by making comparisons between graphs, which types of motions should be compared?
The following two graphs are excerpted from Volume 4 of Glide, Spin, & Jump: The Science of Ice Skating. Notice that these jumps, completed in a purely vertical direction on land, are simpler to analyze, because they lack the horizontal translational motion across the ice.
Discussion Questions
What are the major differences between these graphs?
In these graphs, how
can direction be determined? What direction is up?
In each graph, what
occurs in the vertical
direction?
In the lower graph, what
is the pattern of acceleration in the horizontal plane during the rotations?
In each graph, what sort of tilt (side to side) occurs?
Is it better to locate the wireless device on the stomach or chest? Why?
Describe the role of knee motions during each of the above jumps, and their effects on acceleration.
What is the role of non-relevant movements (such as the motion of breathing) in these graphs, if any?
What is the role of error or random motion in these graphs, if any?
Are these clean (technically correct) jumps? If not, what would the acceleration pattern be during a clean jump?
What would a fall look like in a graph of acceleration?
What would the graphs look like if the jumps were completed on the ice?
Additional free graphs of ice skating are available in a free pamphlet from the publisher's webpage. A humorous cartoon animation of an ice skater, showing approximate force vectors, is available from the publisher's YouTube channel.
The following books from Schottenbauer Publishing contain similar types of graphs and data pertaining to the science of ice skating, figure skating, and hockey:
Physics divides motion into two general types: translational (straight) motion and rotational (curved) motion. Whether it is a figure skater, hockey skater, or puck rotating on the ice, the same laws of physics apply. The graph below (Copyright 2014, All Rights Reserved), excerpted from the book series Glide, Spin, & Jump: The Science of Ice Skatingfrom Schottenbauer Publishing, shows a rod rotating around a central axis.
Discussion Questions
Describe the four variables contained in the graph. What is the range of each variable?
How is position measured in the graph? What is the unit of measurement?
How many times is force applied to the rod?
When force is applied, what happens to the rod?
Why does the rod slow down, and motion stop?
What is the definition of acceleration?
Why does acceleration change so much, when the velocity and position do not?
Additional free graphs are available in a free pamphlet from the publisher's webpage. The following books from Schottenbauer Publishing contain similar types of graphs and data pertaining to the science of ice skating, figure skating, and hockey:
