Sine ruler
A sine ruler is a teaching tool that can be used to determine angles down to 3 "( arcseconds ). For example, two dial gauges are attached to the cone that lies on the ruler , with which a height difference - and thus an incorrect angle - is detected can be.
On the right-hand side, the sine ruler is supported with parallel gauge blocks and the desired angle is obtained between the upper surface of the angle to be tested and the surface on which the ruler stands. How high the parallel gauge blocks under the sine ruler must be is calculated with the aid of the sine function. The ruler is usually 100 mm or 200 mm long to make the calculation easier.
The sine table works according to the same principle as a clamping device .