PLANE CURVES A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z                    HOME ABOUT CATEGORIES SITE MAP COPYRIGHT ADVERTISE CONTACT entire Web this site conchoid The conchoid of Nicomedes – the three cases: a = b (blue curve); a > b (white curve); a < b (red curve) A shell-shaped curve. Given a point A and a curve C, if we pick a point Q on C and draw a line L through A and Q and mark points P and P' on L at some fixed distance in either direction from Q, then the locus of P and P' as Q moves on C is a conchoid. The conchoid of Nicomedes is a conchoid in which the given line is a straight line; i.e. given a line C and a point A we pick a point Q on C, draw a line L through A and Q, and mark P and P' on L at some fixed distance from Q. The conchoid of Nicomedes is the locus of P and P' as Q moves along C. It has the polar equation r = a sec θ + k. The conchoid of de Sluze is the curve with the Cartesian equation a(x - a)(x2 + y2) = k2x2. Related category    • PLANE CURVES Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) BACK TO TOP