| 摘要 |
FIELD: geometry training appliance is meant for studying and demonstration of falling shadows from straight lines on models of surfaces of various types. ^ SUBSTANCE: model of surface is made on a base with its possible replacement. Bar, imitating a straight line, is held in joint sliders of telescopic bars with possible alternation of its height-relative position. Spherical slider with protractor and telescopic spring-loaded rod with writing device on the end, slides freely on the bar, while writing device is held on spherical slider at necessary angle, coinciding with direction of light stream. ^ EFFECT: expanded didactic capabilities. ^ 2 dwg |
