The nephroid (top left) was named
for its similarity to a kidney. It was
first studied by the tireless
Huygens with additional work by
astronomer R.A. Proctor. Its
perimeter is 24 times the radius;
while its area is 12 pi times the
radius squared. For gardeners, the
five-cusped epicycloid is known as a
ranunculoid - it has a perimeter of
48 times the radius and an area of 42
pi times the radius squared. Note
that Freeth's nephroid is actually a
strophoid.
for its similarity to a kidney. It was
first studied by the tireless
Huygens with additional work by
astronomer R.A. Proctor. Its
perimeter is 24 times the radius;
while its area is 12 pi times the
radius squared. For gardeners, the
five-cusped epicycloid is known as a
ranunculoid - it has a perimeter of
48 times the radius and an area of 42
pi times the radius squared. Note
that Freeth's nephroid is actually a
strophoid.
