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).
Explaining the principles of free magnetism and magnetic induction.
| Identifier | ExFiles\Box 35\1\ scan 174 | |
| Date | 11th August 1939 | |
| -4- Contd. FREE MAGNETISM. Where lines of magnetisation reach the surface of the magnetic material, there exists on that surface what is called free magnetism, of polarity according to the direction of the lines and of amount corresponding to their number. Lines of magnetisation may cease and free magnetism may exist inside the magnetic material. Corresponding to the free magnetism, there exists a field of magnetic force, both inside and outside the material, which produces numerically the same magnetic induction in the space. The actual magnetic induction in the material is the resultant of the magnetic induction due to the free magnetism, in the space occupied by the material, and the magnetisation of the material itself. We are supposing at the moment that there is no other magnetic influence than that of the material itself. The magnetic induction outside the material is, of course, the same numerically as the magnetic force due to the free magnetism. Magnetic induction is always continuous across any surface, hence the outside induction may be looked upon as partly/a continuation of the inside magnetisation and partly as a continuation of the induction of the inside space. Contd. | ||