Can a Strong Magnet Induce EMF in a Copper Wire Solenoid from a Distance?

AI Thread Summary
The discussion centers on whether a strong magnet can induce EMF in a copper wire solenoid from a distance, particularly in relation to Faraday's law. It is generally believed that EMF is primarily induced when a magnet passes through a coil rather than just near it. The strength of the magnet and its distance from the solenoid are critical factors, with some suggesting that a sufficiently strong magnet could still induce EMF even at a distance of 20 cm. The orientation of the magnet's movement, whether parallel or perpendicular to the wire, may also influence the induced EMF. Ultimately, the consensus leans towards the necessity of a magnet passing through the coil for significant EMF induction.
Abhilash Goyal
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Is it necessary to pass magnet through solenoid in Faraday's law experiment. If not, then how much emf could be induced if a normal bar magnet crosses a copper wire solenoid from a distance of approx 1 meter.
 
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Faraday's law is strictly for coiled wire I thought. So I don't think emf would be induced if a normal bar magnet crosses a copper wire. If it did, then it would probably depend on which way the magnet is moving (parallel to the wire or perpendicular to the wire). But as far as I know it has to be a magnet passing through a coil.
 
RaulTheUCSCSlug said:
Faraday's law is strictly for coiled wire I thought. So I don't think emf would be induced if a normal bar magnet crosses a copper wire. If it did, then it would probably depend on which way the magnet is moving (parallel to the wire or perpendicular to the wire). But as far as I know it has to be a magnet passing through a coil.

Just take an example, a copper solenoid(closed circuit connected to a voltmeter) is kept vertically on a table, and a strong bar magnet is passed near it approx 20 cm away, would there be any reading in the voltmeter ?
 
Abhilash Goyal said:
Just take an example, a copper solenoid(closed circuit connected to a voltmeter) is kept vertically on a table, and a strong bar magnet is passed near it approx 20 cm away, would there be any reading in the voltmeter ?
I believe it'll depend on how strong the magnet is..The coil is having air core which has very low permeability..If the magnet is strong enough (I don't know exactly how much),it will induce emf in the coil even being away from the coil..
 
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