An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

A device consisting of a length of electrical wire wound in a spiral to provide magnetic field by → electromagnetic induction.

Maybe from M.E. cull, from M.Fr. culier, coillir "to gather," from L. colligere "to bind together," → collect.

Picé "a curled, a twisted figure or object," from picidan "to twist, invove, enttwine, coil."

The change of direction undergone by the electron in the → Compton effect. The scattered photon and the collided electron move in different directions from that of the incident photon.

→ Compton; → recoil.

A device for producing high-voltage pulses by means of → electromagnetic induction. It consists of a primary coil of a few turns of wire, wound on an iron core, and insulated from a secondary coil of many turns which surrounds it coaxially. The current in the primary, which is interrupted periodically, sets up a magnetic field, first big, then zero. This changing field induces a large voltage in the secondary.

→ induction; → coil.

1) To draw back; to rebound or fly back.
2) An act of recoiling. → Compton recoil.

M.E. recoilen, reculen, from O.Fr. reculer "to go back, recede, retreat," from V.L. *reculare, from L. → re- "back" + culus "backside."

Paszadan, from pas-, → back-, + zadan "to strike, beat, dash against," from Mid.Pers. zatan, žatan, O.Pers./Av. jan-, gan- "to strike, hit, smite, kill" (jantar- "smiter"), Skt. han- "to strike, beat" (hantar- "smiter, killer"), cf. Gk. theinein "to strike," L. fendere "to strike, push," Gmc *gundjo "war, battle;" PIE *g^when- "to strike, kill."

An → induction coil which was a forerunner of today's automobile ignition coil. It consists of two coils wound on a single → iron core, and uses an → alternating current produced by a break-wheel to induce a high-voltage current in the secondary coil.

After Heinrich Daniel Ruhmkorff (1803-1877), a German-born instrument maker, who settled in Paris in 1819 for the rest of his life; → coil.