Radius of a Circle
Radius, abbreviated as r, of a circle is a line segment between the center point and a point on a circle or sphere.
Radius of a Circle formulas
\(\large{ r = \frac{D}{2} }\) | |
\(\large{ r = \frac{C}{2 \; \pi} }\) | |
\(\large{ r = \frac{ 2 \; A }{ C } }\) | |
\(\large{ r = \sqrt{ \frac{A}{\pi} } }\) | |
\(\large{ r = \sqrt{ \frac{G \; m}{g} } }\) | |
\(\large{ r = \frac{ l_a }{ \theta } }\) | |
\(\large{ r = \sqrt{ \frac{ 2 \; A_s }{ \theta \; - \; sin \; \theta } } }\) | |
\(\large{ r = \sqrt{ \frac{ c^2 }{ 4 } + h_c^2 } }\) | |
\(\large{ r = h_s + h_c }\) | |
\(\large{ r = \sqrt{ \frac{ 2 \; A_{se} }{ \theta } } }\) | |
\(\large{ r = \frac{ v^2 }{ a_c } }\) | (centripetal acceleration) |
\(\large{ r = \frac { v_c \; t }{ 2 \; \pi } }\) | (circular velocity) |
\(\large{ r = \frac{ 2 \; g \; m }{ v_e } }\) | (escape velocity) |
\(\large{ r = \sqrt{ \frac{t_s^2 \;G\; m}{4\; \pi^2} } }\) | (Kepler's third law) |
Where:
Units | English | Metric |
\(\large{ r }\) = radius | \(\large{ in }\) | \(\large{ mm }\) |
\(\large{ l_a }\) = arc length | \(\large{ in }\) | \(\large{ mm }\) |
\(\large{ A }\) = area | \(\large{ in^2 }\) | \(\large{ mm^2 }\) |
\(\large{ \theta }\) (Greek dymbol theta) = central angle | \(\large{ deg }\) | \(\large{ rad }\) |
\(\large{ a_c }\) = centripetal acceleration | \(\large{\frac{deg}{sec^2}}\) | \(\large{\frac{rad}{s^2}}\) |
\(\large{ v_c }\) = circular velocity | \(\large{\frac{ft}{sec}}\) | \(\large{\frac{m}{s}}\) |
\(\large{ C }\) = circumference | \(\large{ in }\) | \(\large{ mm }\) |
\(\large{ s }\) = chord | \(\large{ in }\) | \(\large{ mm }\) |
\(\large{ s }\) = chord circle centerto midpoint distance | \(\large{ in }\) | \(\large{ mm }\) |
\(\large{ C }\) = diameter | \(\large{ in }\) | \(\large{ mm }\) |
\(\large{ v_e }\) = escape velocity | \(\large{\frac{ft}{sec}}\) | \(\large{\frac{m}{s}}\) |
\(\large{ g }\) = gravitational acceleration | \(\large{\frac{ft}{sec^2}}\) | \(\large{\frac{rad}{s^2}}\) |
\(\large{ m }\) = mass | \(\large{lbm}\) | \(\large{kg}\) |
\(\large{ \pi }\) = Pi | \(\large{3.141 592 653 589 793...}\) | |
\(\large{ A_{se} }\) = sector area | \(\large{ in^2 }\) | \(\large{ mm^2 }\) |
\(\large{ A_s }\) = segment area | \(\large{ in^2 }\) | \(\large{ mm^2 }\) |
\(\large{ h_s }\) = segment height | \(\large{ in }\) | \(\large{ mm }\) |
\(\large{ t }\) = time | \(\large{ sec }\) | \(\large{ s }\) |
\(\large{ t_s }\) = time (satellite orbit period) | \(\large{ sec }\) | \(\large{ s }\) |
\(\large{ G }\) = universal gravitational constant | \(\large{\frac{lbf-ft^2}{lbm^2}}\) | \(\large{\frac{N - m^2}{kg^2}}\) |
\(\large{ v }\) = velocity | \(\large{\frac{ft}{sec}}\) | \(\large{\frac{m}{s}}\) |