Chapter R: Ra Rupture Point

Ra

radium (element)

radial acceleration

ROTATION

radial velocity

ROTATION

radian

the angle in a circle where the radius of the arc equals the length of the arc, specifically 57 and 17.75 min.

radian =

0.159155 circle	0.6366 quadrant
57.29578 (angular)	0.159155 rev
3438 min (angular)	2.063 E + 05 sec (angular)

radian/second =

3437.75 (angular)/min	9.549 rev/min
57.29578 (angular)s	0.1592 rev/s

radian/second/second =

573 rev/min 2	0.1592 rev/s 2
9.549 rev/min/s

radiant heating

See also HEAT TRANSFER.

radiation factor

See also HEAT TRANSFER.

radius of gyration, plane area

as related to the moment of inertia of the plane surface about a referenced axis. It is the equivalent of concentrating the entire area of the plane surface at a point a distance k from the referenced axis, where

A	= area, in. 2
I	= moment of inertia, in. 4
k	= radius of gyration, in.

CD	radius of gyration:

radius of gyration for various sections: refer to ANGLE; CHANNEL; CIRCLE; ELLIPSE; HEXAGON; OCTAGON; PARABOLA; RECTANGLE; SQUARE; TEE; TRAPEZOID; TRIANGLE; Z BAR.

radius of gyration, solid

as related to the moment of inertia of the solid, in units of mass, about a referenced axis. It is the equivalent of concentrating the mass of the body a distance k from the referenced axis, where

I	= moment of inertia, slug-ft 2
k	= radius of gyration, ft
m	= mass, slugs
W	= weight, lb

CD	radius of gyration:

radius of...