Magnetic Flux (Induction - Magnet through a coil)

Click For Summary
SUMMARY

The forum discussion centers on the experiment of dropping a magnet through a solenoid and analyzing the resulting voltage vs. time graph. The first experiment, with the north pole facing down, produced a negative first peak of 0.0137 and a positive second peak of 0.0141. The second experiment, with the south pole facing down, yielded a positive first peak of 0.01095 and a negative second peak of 0.0117. The discussion concludes that the areas under the voltage curves, representing magnetic flux, should be equal in magnitude despite the differing signs, supporting the conservation of energy as described by Lenz's Law and Faraday's Law.

PREREQUISITES
  • Understanding of electromagnetic induction principles
  • Familiarity with Lenz's Law and Faraday's Law
  • Basic knowledge of voltage and current measurements
  • Ability to interpret graphs in the context of physics experiments
NEXT STEPS
  • Study Maxwell's equations in detail to understand their application in electromagnetic induction
  • Learn about the mathematical derivation of Lenz's Law and its implications
  • Explore the concept of magnetic flux and its calculation in various scenarios
  • Investigate the effects of different orientations of magnets in solenoid experiments
USEFUL FOR

Physics students, educators, and researchers interested in electromagnetic theory, particularly those studying induction and conservation laws in electrical circuits.

ManMonkeyFish
Messages
5
Reaction score
0
Is the incoming flux (first peak) equal in magnitude to the outgoing (second peak) flux? Why?

A magnet was dropped through a solenoid, this experiment was completed twice, a graph of Voltage (V) vs. Time (t) was made for each experiment. The area under each curve is defined to be equivalent to the Magnetic flux.

1st time the magnet was dropped with the north pole facing down. The negative first peak had A = 0.0137 with current moving CCW and the second peak was positive with A = 0.0141 with the current moving CW.

2nd time the magnet was dropped with the south pole facing down. The first peak was positive with A = .01095 with current moving CW and the second peak was negative with A = 0.0117 and current moving CCW.


The percent differences are low enough to be dismissed ( I'm assuming ) and the respective area's should have equal magnitudes. The graph shows that the voltage spikes higher in the second peaks but over a shorter period of time. Potential energy is conservative so the voltages should have equal magnitudes with different signs. I can not however find a way to back it up other using any of Maxwell's equations. I have used Lenz's law as my basis as well as attempting to find a derivative of Amperes Law to back up my answer to no avail.
A small hint or push in the right direction ( or a slap if I am completely wrong :redface:) would be greatly appreciated
 
Physics news on Phys.org
Well, you could have either turned the solenoid upside down or the magnet upside down (relatively). You chose to turn the magnet over, and found that energy is conserved in both cases (something Lenz's law will tell you). If all you have to do is show that as your data has, mostly, confirmed conservation laws then just back it up with Lenz's/Faraday's Law.
 

Similar threads

  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 8 ·
Replies
8
Views
2K
Replies
11
Views
3K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
Replies
12
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
Replies
5
Views
3K
  • · Replies 2 ·
Replies
2
Views
4K
  • · Replies 4 ·
Replies
4
Views
2K