» Resistance Box (1-4 K Ohm) (0180)
Immagini
DESCRIPTION
Exhibit 180 is a resistance box containing a series of reels on each of which is wound a coil of wire of known resistance. On the outside top, there is a series of brass blocks. The two ends of the wire on each reel is welded to two contiguous blocks. The winding of the resistance wire is anti-inductive, that is half the winding is in one sense and the other half in the opposite sense so that the current which passes cannot generate a net magnetic field. There are brass keys which can short circuit any of the reels. The blocks and the keys have negligible resistance. Thus the resistance of the box in a circuit is equal to the sum of the resistances (written on the box) associated with the withdrawn keys.
ISCRIZIONI
- Inciso su una targhetta fissata con viti alla cassetta: 1 Ω =1,063 Q.E. EDELMANN MUNCHEN
BIBLIOGRAPHY
- [1] E.Perucca - Fisica Generale e sperimentale - Vol. II - UTET (Torino) 1942
Dati Catalografici
| Data di costruzione: | --- |
|---|---|
| Data di carico: | ignota |
| Nr. Inventario: | Ignoto (Ignoto) |
| Costruttore: | Edelmann |
| Materiale: | ottone, legno, avorio, bakelite |
| Dimensioni: | 35,7 cm x 13,8 cm x 17,5 cm |
| Conservazione: | ottimo |