Hockey Stop Deceleration/Friction Analysis

When a skater is traveling at a high speed and wants to stop quickly, one action that the skater and perform is called a hockey stop. In this motion, the skater turns their skates so that the skate blades are perpendicular to the motion of the skater. The blades "dig in" to the ice and have a high coefficient of kinetic friction which allows the skater to decelerate rapidly and come to a stop in a short distance. This transition from a very low coefficient of kinetic friction when the blades are parallel to the motion to a very high coefficient of kinetic friction when the blades are perpendicular allows the skater to travel at a high speed and then quickly come to a controlled stop.
While experimenting with this on my friend's small temporary ice rink that he has in his backyard, I decided to measure his deceleration as he went from a high speed to a quick stop.

Using the 4ft (1.22 meters) side boards as a metric, the deceleration can be measured from a video clip of a hockey stop.

In the video, a hockey stop is completed over a duration of less than 2 seconds and in a distance of less than 2 meters.

This graph shows the displacement over time of the skater's deceleration.

From a linear fit graph of this data, the hockey stop produces an acceleration of -1.521 m/s.

Because the skater weighs ~75kg and F=ma, we can calculate the force required for this deceleration to be ~114 N.

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