Descriptive geometry . l it lies in //. The figure is left to the process is the same as described in § 70, and shown pic-torially in Fig. 08. The statement of § 76 may be modified tomeet the present situation, as follows. If a point a Lying inplane Q, be revolved about IIQ as an axis, the circular pathof the revolving point will project on //as a straight line per-pendicular to IIQ. If the point a be revolved into //, itsrevolved position will be at a distance from H(J equal to thetrue distance of the point from HQ. An analogous statement applies to the revolution of a pointabout
Descriptive geometry . l it lies in //. The figure is left to the process is the same as described in § 70, and shown pic-torially in Fig. 08. The statement of § 76 may be modified tomeet the present situation, as follows. If a point a Lying inplane Q, be revolved about IIQ as an axis, the circular pathof the revolving point will project on //as a straight line per-pendicular to IIQ. If the point a be revolved into //, itsrevolved position will be at a distance from H(J equal to thetrue distance of the point from HQ. An analogous statement applies to the revolution of a pointabout VQ into V. 139 140 DESCRIPTIVE GEOMETRY [XV, § 138 Construction (Fig. 217). Let a, lying in the plane Q, be thegiven point, and let it be required to revolve a about HQ intoH Erom ah draw the line aheh perpendicular to HQ, and pro-duce the line indefinitely. This line is the //-projection of thecircular path of the revolving point, the center of revolutionbeing the point e (eh) lying on HQ. The line aheh is one pro-.
Size: 1292px × 1933px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectgeometrydescriptive
