From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
The determination of the specific resistance of a tungsten rod.
| Identifier | ExFiles\Box 35\5\ scan 131 | |
| Date | 1st October 1920 | |
| RFC. X. 2894 1.10.20. X.2894 - SPECIFIC RESISTANCE OF TUNGSTEN ROD The specific resistance of a rod of tungsten .2365 cms.dia. was determined as follows. A milli-voltmeter was connected across 10 cms. of its length and a current was sent through by connections outside the milli-voltmeter terminals, from a two volt cell and through a variable resistance and ammeter. Readings of the volt drop for various currents were taken, which gave a resistance of .00121 ohm. This works out to 5.94 microhms per cubic cm. which is the specific resistance. At no time during the test did the temperature of the rod increase appreciably. R.J.A. | ||