That is a logarithmic (or equiangular) spiral. The “characteristic angle is the “flare” angle outwards from a 90 deg circumference woulch would touch a radius at any point. The equation for radius at any angle is:
r = ae^[b*theta]
or
r = e^[theta* cotk]
These occur widely in nature. They describe such things as the arrangement of seed-positions in radially-symmetrical flowers, the shape of a revolving spiral galaxy, and the path of a water molecule sprayed out of a revolving hose or sprinkler at constant radial and angular velocities.
It only works for me when i have my spectacles on.
How odd, it appears to be rotating slowly anti-clockwise when I have my specs on (I am short sighted), but not when they are off.
Me too. However, I’ve just ocme back from swimming, and it doesn’t rotate at the moment unless I will it to.
That is a logarithmic (or equiangular) spiral. The “characteristic angle is the “flare” angle outwards from a 90 deg circumference woulch would touch a radius at any point. The equation for radius at any angle is:
r = ae^[b*theta]
or
r = e^[theta* cotk]
These occur widely in nature. They describe such things as the arrangement of seed-positions in radially-symmetrical flowers, the shape of a revolving spiral galaxy, and the path of a water molecule sprayed out of a revolving hose or sprinkler at constant radial and angular velocities.
It doesn’t rotate at all for me….wonder why? I just see it as a graph.
Ahhhhh….you have to shift the aim of your eyes rapidly right and left. Then, it does.
David, how can a series of concentric circles be a spiral?