The Laws of Faraday and Lenz (152)
BlackBoard Notes

• Note: Remember to print out worksheets (updated July 2025) and Magnet Warning signs (4 - two outside lab door, one above horseshoe magnet, one on blackboard), and set power supply in stockroom to 6 volts!

======================= Photo - Click for a Larger Version =============================

======================= First Board Section =============================

• Faraday's Law:
  • 
• (Place magnetic field warning sign in this section; use four small magnets, found in upper corner of blackboard)
• (add this, if needed) Next week: Bring Ohm's Law journal and KaliedaGraph graph file to lab!

======================= Second Board Section =============================

• Galvanometer: Detects the presence and direction of I

  

• Does the needle point left or right in this circuit?
• You MUST use the 100 kΩ resistor here!!

======================= Third Board Section =============================

• The coil: Draw sketches on worksheet

• (Write the following on sketch!)
  • Draw needle pointing right or left
  • Move bar magnet halfway in or out of coil!
• In all cases (permanent magnet and electromagnet), what is the relationship between change in φ_B (increasing or decreasing) and the direction of B and B_IND (the same or opposite)?

======================= Fourth Board Section =============================

• Exit quiz:
  • Identify north pole of unknown magnet using Faraday/Lenz
    • A lab practical skill!
  • By yourself! No notes, no compass!
  • Same galvanometer, different coil and connection!

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Revised: 21 Jul 2025

Canton, NY 13617