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).
Page explaining the principles of magnetic fields, magnetisation, and magnetic induction.
| Identifier | ExFiles\Box 35\1\ scan 173 | |
| Date | 11th August 1930 | |
| R.R. Fds 1980 T. (S.H. 159. 11-8-30) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2800 -3- Contd. the magnetic material was brought there, but it is the original field modified by a new field of magnetic force due to free magnetism produced on and in the magnetic material itself. In fact the actual resultant magnetic force anywhere, is the resultant of two components one due to original field, the other due to induced magnetisation. The lines of induces magnetisation themselves are in the direction of the modified and not in the direction of the original field. Thus, when dealing with magnetic principles, we are up against a sort of vicious circle. The magnet-isation of the above material is such as to be the direct result of a field of force which is itself the resultant of the original field and the field due to the magnetisation. MAGNETIC INDUCTION. (3) The magnetic induction at any point of a material is always the sum of the magnetic induction in the space at the point (which is numerically the same as the magnetic force at the point) and the magnetisation of the material at the point, thus :- B = H + M.{Mr Moon / Mr Moore} It consists of two parts, one belonging to the space, the other to the material. In non-magnetic matter M = 0, and the induction B = magnetic force H numerically. Contd. | ||