Voltage or current in solenoid?

AI Thread Summary
In solenoids, the force generated is primarily dependent on the current rather than the voltage, as the magnetic field strength is directly related to the current flowing through the wire. According to the equation B = μ n I, where B is the magnetic field, μ is the magnetic constant, n is the number of turns per unit length, and I is the current, it is clear that current is the key factor. Voltage is necessary to establish and maintain the current, but it does not directly influence the magnetic field strength. The relationship between voltage, current, and resistance must be considered, as they all play a role in the overall function of the solenoid. Understanding this interplay is crucial for effectively designing and building solenoids.
falling cat
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Hi everyone,

I'm having some fun building solenoids for a project. I can't just leave "well enough" alone... I want to know how these things really work! I understand the concepts behind Faraday's laws, current in a wire, etc...

What I would like to find out is which gives more force to the solenoid, V or I? I know Ohm's law says I can't raise one without the other... But does the force depend on the voltage or current, assuming the number turns remains constant?

Thanks!
 
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What "force" are you asking about? If you are asking about the induced magnetic field through the solenoid, then it depends solely on current. The equation is given by: B = μ n I, where μ is the magnetic constant (permeability of free space), n is the number of turns per unit length (turn density), and finally I is the current. Think of it like this: Movement of charges (current) induces the magnetic field, not the energy carried per charges (voltage). Hopefully this was the question you were asking, if it were not, then you might want to consider rephrasing the question.
 
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falling cat said:
What I would like to find out is which gives more force to the solenoid, V or I?
The current is directly related to the magnetic field but, to cause a current to flow, a Voltage is needed.
It's a matter of considering all the variables. n, the number of turns will affect the Voltage that's required to pass a given amount of current because the resistance of the length of wire affects the current. There isn't a 'heirarchy' of variables; they are all relevant.
 
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Thanks for your insight guys!

The way both of you put it makes sense- current makes the field stronger, but the voltage is necessary to keep the current constant for a certain length.

Thanks again!
 
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