Ads
related to: figuring radius and diameter worksheet free download word
Search results
Results From The WOW.Com Content Network
Since the diameter is twice the radius, the "missing" part of the diameter is (2r − x) in length. Using the fact that one part of one chord times the other part is equal to the same product taken along a chord intersecting the first chord, we find that (2r − x)x = (y / 2) 2. Solving for r, we find the required result.
as one would expect. This is equivalent to the above definition of the 2D mean diameter. However, for historical reasons, the hydraulic radius is defined as the cross-sectional area of a pipe A, divided by its wetted perimeter P, which leads to =, and the hydraulic radius is half of the 2D mean radius. [3]
Alternatively, the closely related mean diameter (), which is twice the mean radius, is also used. For a non-spherical object, the mean radius (denoted R {\displaystyle R} or r {\displaystyle r} ) is defined as the radius of the sphere that would enclose the same volume as the object. [ 1 ]
The radius of a circle is perpendicular to the tangent line through its endpoint on the circle's circumference. Conversely, the perpendicular to a radius through the same endpoint is a tangent line. The resulting geometrical figure of circle and tangent line has a reflection symmetry about the axis of the radius.
The radius of the incircle is related to the area of the triangle. [18] The ratio of the area of the incircle to the area of the triangle is less than or equal to π / 3 3 {\displaystyle \pi {\big /}3{\sqrt {3}}} , with equality holding only for equilateral triangles .
If and are the radii of the small semicircles of the arbelos, the radius of an Archimedean circle is equal to = + This radius is thus = +.. The Archimedean circle with center (as in the figure at right) is tangent to the tangents from the centers of the small semicircles to the other small semicircle.
Let A′ be the point opposite A on the circle, so that A′A is a diameter, and A′AB is an inscribed triangle on a diameter. By Thales' theorem, this is a right triangle with right angle at B. Let the length of A′B be c n, which we call the complement of s n; thus c n 2 +s n 2 = (2r) 2. Let C bisect the arc from A to B, and let C′ be the ...
To calculate a circle's perimeter, knowledge of its radius or diameter and the number π suffices. The problem is that π is not rational (it cannot be expressed as the quotient of two integers ), nor is it algebraic (it is not a root of a polynomial equation with rational coefficients).