Draw a ray from the object to the lens that is parallel to the principal axis. Once through the lens, the ray should pass through the principal focus. Draw a ray which passes from the object through ...

When light moves from air into glass or plastic it is refracted close refractionProcess by which a wave changes speed and sometimes direction upon entering a denser or less dense medium, eg a light ...

A DISCUS SIGN on the determination of equilibrium diagrams by X-ray methods arranged by the Institute of Physics was held at the Royal Institution, London, on September 22. The chairman, Sir Lawrence ...

SCREENING and spin doublets in X-ray spectra are matters of great significance. The formation of these doublets in X-ray diagram lines is now well known and has received satisfactory theoretical ...