Protractor
The protractor is a tool used to measure angles. It usually has marks with labels of the degrees. Protractors are usually half circles or full circles.
Protractor Media
Goniometer made by Develey le Jeune in Lausanne, late 18th–early 19th century
A half-circle protractor marked in degrees (180°).
A half-circle bevel protractor
A universal bevel protractor.
Manual (1), and Mitscherlich's optical (2) goniometers for use in crystallography, c. 1900
Surface scientists use a contact angle goniometer to measure contact angle, surface energy and surface tension.
In a contact angle measurement, the angle between the droplet and solid surface indicates the wettability of the surface.
Surface tension exists because the molecules inside a liquid experience roughly equal cohesive forces in all directions, but molecules at the surface experience larger attractive forces toward the liquid than toward gas.
A miniature electro-mechanical goniometer stage. This type of stage is used primarily in the field of lasers and optics.
Electronic protractor for quick and reliable measurement and duplication of angles - just take measurements direct from drawings and then transfer where they are needed.
