======Electromagnetic Induction======


<WRAP right box>
**Materials: **{{$demo.materials_description}}\\
**Difficulty: **{{$demo.difficulty_description}}\\
**Safety: **{{$demo.safety_description}}\\
\\
**Categories:** {{$demo.categories}}
\\


**Alternative titles:** Faraday’s Law – Classic Induction Demo
</WRAP>

====Summary====                   
{{$demo.summary}}



====Procedure====   
  - Connect a solenoid in parallel to an electrometer.  
  - Insert the bar magnet into the solenoid and then remove it quickly.  
  - Observe the electrometer as the needle or digital readout changes, showing an induced voltage.  
  - Repeat with different speeds: move the magnet slowly to produce a weak emf, and more quickly to produce a stronger emf.  
  - Reverse the magnet’s pole and note the opposite direction of the induced voltage.




====Links==== 
Electromagnetic induction - ibPhysicsHelp: 
{{youtube>hajIIGHPeuU?}}\\

Demonstration of Electromagnetic Induction - IGCSE Physics - Chris Gozzard (That Physics Guy): 
{{youtube>_k0JJpJ4_sw?}}\\

📄 Faraday’s Law – Electromagnetic Induction - UCSC Physics Demonstration Room: [[https://ucscphysicsdemo.sites.ucsc.edu/physics-5c6c-demos/electromagnetism/faradays-law-electromagnetic-induction/]]\\

====Variations====
  * Compare results using a weak bar magnet versus a strong neodymium magnet.  
  * Change the angle of the magnet’s motion relative to the solenoid axis.  
  * Use solenoids with different numbers of coils to show how more loops increase the induced emf.



====Safety Precautions====
  * Handle magnets carefully to avoid pinching fingers or damaging equipment.
  * Do not connect the solenoid directly to a power source in this setup.  
  * Use proper supports to prevent the solenoid or stand from tipping over.




====Questions to Consider====
  * Why does moving the magnet quickly produce a stronger induced voltage? (Faster motion causes a faster change in magnetic flux, producing a larger emf.)  
  * What determines the direction of the induced voltage? (Lenz’s law states that the induced emf opposes the change in magnetic flux.)  
  * Why is no emf induced when the magnet is held still in the solenoid? (There is no change in magnetic flux, so no induction occurs.)  
  * How does increasing the number of coils affect the induced emf? (More coils increase the total flux linkage, producing a stronger induced voltage.)