184_notes:perm_mag

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184_notes:perm_mag [2021/06/16 18:50] bartonmo184_notes:perm_mag [2021/07/05 21:52] (current) schram45
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 Since Earth's field is relatively constant, we can actually use Earth's magnetic field to measure the magnetic field from other sources. So say we have a current that runs perpendicularly to Earth's B-field (shown as out of the page/screen in the figure). If we consider a point above the wire (Point P), the Earth's magnetic field will (always) point toward the geographic north. However, the current will produce a B-field at Point P that points to the west (or $-\hat{x}$) using the right hand rule (point your fingers out of the page then curl them toward Point P - your thumb should be pointing to the left). So if we put the compass at Point P, we would expect it to point in the direction of the //**net**// magnetic field (or to the north west in this case). The example below will go into more detail about how we can use that to calculate the size of the magnetic field from the wire. Since Earth's field is relatively constant, we can actually use Earth's magnetic field to measure the magnetic field from other sources. So say we have a current that runs perpendicularly to Earth's B-field (shown as out of the page/screen in the figure). If we consider a point above the wire (Point P), the Earth's magnetic field will (always) point toward the geographic north. However, the current will produce a B-field at Point P that points to the west (or $-\hat{x}$) using the right hand rule (point your fingers out of the page then curl them toward Point P - your thumb should be pointing to the left). So if we put the compass at Point P, we would expect it to point in the direction of the //**net**// magnetic field (or to the north west in this case). The example below will go into more detail about how we can use that to calculate the size of the magnetic field from the wire.
 ==== Examples ==== ==== Examples ====
-[[:184_notes:examples:Week9_earth_field|Using the Earth's Magnetic Field for Measurements]]+  * [[:184_notes:examples:Week9_earth_field|Using the Earth's Magnetic Field for Measurements]] 
 +    * Video Example: Using Earth's Magnetic Field for Measurements 
 +{{youtube>0kc-otyFZY0?large}}
  • 184_notes/perm_mag.txt
  • Last modified: 2021/07/05 21:52
  • by schram45