It is similar to what happens when you swing a yo-yo around in a circle above your head and the string breaks. As long as the string is in tact the yo-yo continues in a circular motion. But when the string breaks the resistance of the string is eliminated allowing the inertia of the yo-yo to travel in a linear fashion. This is the same action that occurs when using an old fashioned sling and stone as a weapon.

If the kick is glancing off the target at an angle it is because the person is not timing the kick correctly once they have rotated to their target. It is a practiced technique to be able to time the kick during the rotation and direct all energy into the linear strike. The timing of the kick should be adjusted to accommodate any change in the speed of the rotation. Note: In actuality, the faster the rotation the more power can be generated into the kick. But as I mentioned, the ability to change the circular momentum into the linear strike is based on the timing of the initiation of the kick as you rotate to, and focus on, your target.

https://www.youtube.com/watch?feature=player_embedded&v=Zs4uQ6DfKV8





This is a spinning side kick you spin around and then throw a linear kick.





Im not sure how the s[pin/turn adds force to the linear kick,can you tell how it does IIF it does?





My guess or theory would be that so long as there not too much spin the spin will add force to the linear kick, because the force will make a slightly curved straight is line.





BUT if you spin too much or too powerfully the force of the spin will make the straight lined force into more of a lower case letter j (jay) shape and thats why it will skim off the opponents body and not do any damage?





Is that right?





So the more linear force I can get the more I can spin to add power, but if I dont have enough linear power the spin will reduce not increase the force of the kick?







Can you work this out are you smart enough to workout how the body is connected and how the forces of physics act upon the body?