noun
definition
An epicycloid with exactly one cusp; the plane curve with polar equation \rho = 1 + \cos\,\theta - approximately heart-shaped
adjective
definition
Having this characteristic shape
definition
(of a microphone) sensitive in front, but not behind or at the sides
Examples of cardioid in a Sentence
The form of the limacon depends on the ratio of the two constants; if a be greater than b, the curve lies entirely outside the circle; if a equals b, it is known as a cardioid; if a is less than b, the curve has a node within the circle; the particular case when b= 2a is known as the trisectrix.
This may be readily accomplished geometrically or analytically, and it will be found that the envelope is a cardioid, i.e.
The two ' bulbs ' shown here are directly attached to the main cardioid.
Examples A classic style of microphone for speech recording in interview situations is a hand-held dynamic cardioid microphone.
In the figure (1) is a limagon, (2) the cardioid, (3) the trisectrix.
The epicychid when the radii of the circles are equal is the cardioid (q.v), and the corresponding trochoidal curves are limacons.
It is a double mirror system, whose reflecting surfaces are a sphere a and a cardioid b.
The combination of rays is also sufficient in practice if the cardioid surface is replaced, by a spherical one.