Techniques>Blocks>Physics of blocking

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Physics of blocking

Intro

As you reduce the distance between yourself and your attacking opponent, the less impact you feel from blocking an attack, even if the block misses the attacking arm or leg, the impact of the attack will be reduced. This may be explained by a formula for linear velocity as it relates to angular velocity.

Angular velocity

Angular velocity is simply the speed that a rigid object takes on as it rotates about a fixed point. For example, in a round kick, assume that the leg (rigid object) rotates from the hip (the fixed point). The formula for angular velocity is defined as follows:

a = 0 / t

Where "0" represents the angle of rotation and t represents the time taken to rotate through that angle. The units for angular velocity could be in degrees per minute or rotations per minute or, more appropriately for the kicker, in degrees per second. Angular velocity has a direct relationship with the angle of rotation.

If the kick can accelerate through a greater rotation, it will damage the target more when it contacts it. If the blocker anticipates and steps deeper into the kick's path, the angular speed of the leg is reduced and thus the impact of the leg is reduced.

Linear velocity

Linear velocity, as it relates to its angular velocity counterpart, is the speed of any point on the rotating body (the foot for example) and is proportional to the radial distance from the fixed point to that point. Think about cracking a whip. The speed at of the handle is relatively slow while the tip moves so fast it breaks the sound barrier and snaps. The formula for linear velocity is defined as follows:

v = a x r

Where "a" is the angular velocity as before.

If you decrease the distance r between of rotating leg that is attacking (the distance from the hip to the foot), the speed at which the foot hits you is reduced. If the blocker anticipates and steps deeper into the kick's path, the linear speed of the leg is reduced and thus the impact of the leg is reduced.

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