On this day in history, Columbus discoveredâ¦. the perfect meatball wink emoticon. Little known fact: Also on this day he discovered Spaghetti Warehouse and their $6 World Famous Spaghetti & Meatball Entree with sourdough bread and choice of soup or salad!
Relevance. Rating Newest Oldest. Best Answer: In a generator, residual magnetism, also known as 'remanence' or remanent flux, is due to the hysteresis of the magnetic material in the core. When the current is removed, the magnetic flux often remains at some non-zero value. This is a characteristic phenomenon of ferromagnetic materials.
Stockbyte/Stockbyte/Getty Images. A permanent magnet is a piece of iron or a similar metal having its own magnetic field. Under ideal conditions, it will retain its magnetic strength for many years.Frequent drops, impacts or high temperatures weaken it.agnetic Circuit. A magnetic field holds its strength best when the entire magnetic loop, or circuit, passes through a ferromagnetic metal at all points. A horseshoe magnet has an air gap between its two poles; the keeper closes this gap. A bar magnet, left by itself, will lose its strength over several months.