Why the direction of the current is determined by which way you move the magnet

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SUMMARY

The direction of the current induced in a coil is determined by the movement of a magnet due to Lenz's Law, which states that the induced current will oppose the change in magnetic flux. This principle is derived from Faraday's Law of Electromagnetic Induction, which includes a negative sign to indicate this opposition. The discussion highlights the importance of understanding the relationship between moving magnets and induced currents, emphasizing that without a grasp of these fundamental concepts, deeper comprehension is unattainable.

PREREQUISITES
  • Understanding of Faraday's Law of Electromagnetic Induction
  • Familiarity with Lenz's Law
  • Basic knowledge of magnetic fields and electric currents
  • Ability to interpret graphs of current vs. time
NEXT STEPS
  • Study the implications of Lenz's Law in electromagnetic systems
  • Explore practical applications of Faraday's Law in electrical engineering
  • Learn about the behavior of electrons in magnetic fields
  • Investigate the relationship between magnetic flux and induced electromotive force (EMF)
USEFUL FOR

Students of physics, electrical engineers, and anyone interested in the principles of electromagnetism and their applications in technology.

scientist91
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why the direction of the current is determined by which way you move the magnet through the coil?
 
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because there is a negative sign in faraday's law
 
ice109 said:
because there is a negative sign in faraday's law
explain deeper please. Thank you.
 
i almost started to use swear language.
 
so what the fsck do you want?

hm?

there are the graphs, showing the current vs time.
and formulas are neccesary.
what do you want to undertand, if you are not familiar with the basics?
 
mcstar said:
so what the fsck do you want?

hm?

there are the graphs, showing the current vs time.
and formulas are neccesary.
what do you want to undertand, if you are not familiar with the basics?
I am interested about the electrons. I don't need equations.
 
In my imagination (without any formulas or graphs), thing can be like this. Electrons move and create magnetic field. The direction of the field is always perpendicular to the direction of the electron, and let say to the right. It is something like when you run, you hold a board which is 45 degrees off the running derection and facing to the right. then you always create wind to your right hand.
When you have a moving magnetic field, the electron would move so that it creates a M. fiedl that is opposite to the applying magnetic field. And so its moving direction depends on the direction of the field.
 
  • #10
because the current has to oppose the change in flux
because of conservation of energy and i quote from my intro physics book

"Think what would happen if Lenz's law were turned the other way around, that is, if the induced current acted to aid the change that produced it. You would then need to push a stationary magnet only slightly to get it moving, and the action would be self perpetuating..."

and mcstar's explanation is very good.
 

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