The Cherenkov effect A charged particle traveling in a dielectric medium with n>1 radiates Cherenkov radiation if its velocity is larger than the phase velocity of light v>c/n or Î² > 1/n (threshold) The emission is due to an asymmetric polarization of the medium in front and at the rear of the particle, giving rise to a varying electric dipole momentum.
cyclo-. 1. Combining forms relating to a circle or cycle; or denoting an association with the ciliary body. 2. In chemistry, a combining form indicating a continuous molecule, without end, or the formation of such a structure between two parts of a molecule.
A cycloid is the curve defined by the path of a point on the edge of a circular wheel as the wheel rolls along a straight line. It was named by Galileo in 1599 (http://en.wikipedia.org/wiki/Cycloid). A hypocycloid is a curve generated by the trace of a fixed point on a small circle that rolls within a larger circle.It is comparable to the cycloid, but instead of the circle rolling along a line, it rolls within a circle. Use Google to find a wonderful book of Eli Maor, Trigonometric Delights (Princeton, New Jersey).ence, let us find the parametric equations of the hypocycloid. A point on a circle of radius r rolls on the inside of a fixed circle of radius R. Let C be the center of the rolling circle, and P a point on the moving circle.