The Big One will be a great earthquake. An earthquake is the shaking of the ground cause by seismic waves. Almost all earthquakes occur when pent up stress in rocks along large, active faults (like the SAF) is suddenly released as the rock breaks.he Big One will be a great earthquake. An earthquake is the shaking of the ground cause by seismic waves. Almost all earthquakes occur when pent up stress in rocks along large, active faults (like the SAF) is suddenly released as the rock breaks.
  Magnetism is the force generated by any moving charged particle or charged particles. A magnetic field is the result of the motion of a charged particle or charged particles, and this field is generated in no other way. Any time a charged particle moves, it creates a magnetic field around its path of travel.
When the Hall probe is held so that the magnetic field lines are passing at right angles through the sensor of the probe, the meter gives a reading of the value of magnetic flux density (B). A current is passed through the crystal which, when placed in a magnetic field has a  Hall effect  voltage developed across it.hen the force on the charged particles from the electric field balances the force produced by magnetic field, the separation of them will stop. If the current is not changing, then the Hall voltage is a measure of the magnetic flux density. Basically, there are two kinds of Hall effect sensors.