The phrase "a true circle" is correct and usable in written English.
It can be used when discussing geometric shapes, concepts of perfection, or metaphorically to describe something that is complete or unbroken.
Example: "In mathematics, a true circle is defined as the set of all points equidistant from a central point."
Alternatives: "a perfect circle" or "an actual circle".
However, using this design, a catheter with a 0.46 × 10−2 mm4 second moment of area, which is 16% of that of a true circle tube, is fabricated.
If its axis remained stable and if its orbit were a true circle, then the equinoxes and solstices would quarter the year into equal sections.
She arranged to have them made by women in a South African village, with some of the money raised going to South African AIDS groups, a true "circle of life".
Yet the cat is simply unable to judge whether it is a true circle in the sense that it really is what it is supposed to be, namely, a locus of points equidistant from a given point.
It should be noted that a and b are given not by the actual shape of the borehole, but by the nominal shape assuming the original borehole shape is a true circle with a diameter of 116 mm.
By contrast, a human being is able to judge the truth of this thing, insofar as he or she would be able to tell that my drawing is not really and truly a circle, but is at best a good approximation of what a true circle would be.
The optimum value of the second moment of area is 0.18 × 10−3 mm4, which is only 0.63% of that of a true-circle tube.
To consider this, an ideal perfect circle (true circle) is assumed.
True circle, as expected, was essentially impossible to balance, as steering does not correct for misalignment of the tire patch and center of mass.
Steering motions included "balance", in which both wheels move together to steer the tire contacts under the center of mass; and "true circle", in which the wheels steer equally in opposite directions and thus steering the bicycle without substantially changing the lateral position of the tire contacts relative to the center of mass.
