## Tuesday, 20 May 2014

### Tangential forces

Was just musing while I had a work out at the dojo.

If you try and use your arms (lets give them a value of a) then your Ft (Total Force) = a for all a. If you bend your knee, whilst making the near right angle triangle, you create 'free' power from gravity. Resolving horizontal and vertical;

[ignoring friction and considering the back leg a fixed point]

m(your mass[what you call your weight]) * G (gravity, giving your true weight in Newtons) * tan (the hypoteneuse of the triangle created from upright position, the floor and your throw angle) theta  (the smallest angle of that triangle) + b (vector sum of the horizontal component given from back leg pushing, can't be bothered there's enough maths here already).

For those of you who understand all that you can see your arms need to meet your partner 45 degrees from the horizontal relative to the enclosed systems height. For everyone else hopefully you can see that this is clearly going to give you a far bigger number. And the best thing is when you get good enough you can add 'a' on the end of all that.

So lets assume that your weight is bigger than your arm strength. A maximum power Aikido/jujutsu throw that's not down, will give you many times the value of your strength, plus your strength added on the end.

I just thought that was awesome.