A Solenoid, a Moving Magnet, and a Light Bulb -- Will the Light Bulb LIght Up?

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SUMMARY

The discussion centers on the principles of electromagnetism, specifically how a light bulb lights up when a magnet is moved through a coil of wire, known as a solenoid. According to Faraday's Law, the electromotive force (emf) generated is proportional to the rate of change of magnetic flux through the coil. The Lenz Law explains that the direction of the induced current opposes the change in magnetic field, which is crucial for understanding the operation of the circuit. The light bulb illuminates due to the induced current flowing through it, not merely because the solenoid acts as a magnet.

PREREQUISITES
  • Understanding of Faraday's Law of Electromagnetic Induction
  • Familiarity with Lenz's Law and its implications
  • Basic knowledge of electric circuits and current flow
  • Concept of alternating current (AC) generation
NEXT STEPS
  • Study the mathematical derivation of Faraday's Law
  • Explore practical applications of Lenz's Law in electromagnetic devices
  • Investigate the principles of alternating current generation
  • Examine the role of solenoids in various electrical systems
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Students of physics, educators teaching electromagnetism, and hobbyists interested in electrical engineering concepts.

Illuminitwit
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Homework Statement


"A light bulb is connected to a coil of wire. If a magnet is passed back and forth through the coil the bulb will light up. Why?"

Homework Equations


The Lenz Law isn't really an equation, but it states that: "The magnetic field of the induced current is in a direction to produce a field that opposes the charge causing it."
Faraday's Law: emf = -N(∆ΦM / ∆t)
emf is electromotive force,
N is number of loops in the circuit,
∆ΦM is the magnetic field strength,
∆t is the time

The Attempt at a Solution


Here's what I've written so far, but I think it sounds a little strange because I'm not sure I used the concepts and terms correctly:

"The solenoid connected to the light bulb has the ability to act like a magnet if a current is sent through it. When a magnet approaches the solenoid, according to Lenz's law, the magnetic field creates an induced current in the solenoid that produces a magnetic field that opposes the magnetic charge causing it. If the magnet passes back and forth through the coil and continues moving, it creates an alternating current that lights up the bulb."

If you could please read it for me and point out any errors in use of Physics concepts or errors in understanding that would be better explained another way, I'd greatly appreciate it. Thanks! :)
 
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You are confused a bit. You can say that the solenoid has the ability to act like a magnet is a current is sent through it but the creation of the magnetic field by the solenoid is not what lights the bulb. The bulb lights because the induced current runs through it.
 

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