Item no.: WM 01

Trigonometric function-model for an optical-dynamic presentation of the related trigonometrical functions of sin, cos, tan, cot corresponding with the standard-circle (R = 1). In consequence of a manual initiated positiv or negativ rotation of a gear, a pointer-system will be set in motion. To consider the mathematical definitions of any centre-angle, the distances can be measured by a ruler with an inscribed scale, which corresponds with the standard-radius R = 1, to satisfy the values of the belonging trigonometrical functions. According to a gear-drive the fine tune of the centre-angle is precisely guaranteed.