Re: [Phys-l] bound vectors ... or not

[John Denker <jsd@av8n.com>]

On 09/08/2010 10:49 AM, Edmiston, Mike wrote:

> I believe the real device follows the simplified physics much better
> as the line of action approaches being tangent to the edge of the
> disk,

That's for sure.  Everything is much simpler in the
small-angle approximation.

But then you don't need to bother with the slot,
or bother with a strictly linear force motor ...
because an ordinary piston connected to a crank
with ordinary pins is linear in the small-angle
approximation.

The underlying principle remains 100% correct and
useful, but it's not obvious to me how to exemplify
it using pins sliding in slots.

  One simple example of the principle is to attach
  a rocket motor at point A, point B, or point C.
  If the points lie along the same line of action,
  you get the same torque in each case.