Testing the Magnetism of a Solenoid & Galvanometer

AI Thread Summary
When two magnets, one S-N and the other N-S, move towards a solenoid with a hollow core, they induce opposing currents in the solenoid. As they approach each other at the same speed, the currents generated by each magnet cancel each other out. Consequently, the galvanometer connected to the solenoid shows no current. This phenomenon occurs because the magnetic fields from the two magnets are equal and opposite. Therefore, the prediction of no current in the galvanometer is correct.
handsomecat
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suppose you have a solenoid with hollow core connected to a galvanometer.

On one side you have a S-N magnet (ie. the N pole is nearer to the solenoid). On the other side you have a N-S magnet( ie. S pole is nearer to solenoid). ie.

[S - N] [Solenoid] [N - S]

Both magnets are equidistant from the solenoid, and at a distance sufficient for the solenoid to "detect" the magnetic field.

They start moving towards each other at the same speed into the solenoid core and stop at the same time.

My prediction is that there will be absolutely no current shown in the galvanometer. This is because it is impossible to have N poles on both sides of the solenoid to oppose the motion.

As this topic is new to me, is my prediction correct?
 
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handsomecat said:
On one side you have a S-N magnet (ie. the N pole is nearer to the solenoid). On the other side you have a N-S magnet( ie. S pole is nearer to solenoid). ie.

[S - N] [Solenoid] [N - S]

You have a contradition between your text and your graph that you might want to clear-up.
 
Apologies. It should read:

On one side you have a S-N magnet (ie. the N pole is nearer to the solenoid). On the other side you have a N-S magnet( ie. N pole is nearer to solenoid). ie.

[S - N] [Solenoid] [N - S]
 
handsomecat said:
My prediction is that there will be absolutely no current shown in the galvanometer. This is because it is impossible to have N poles on both sides of the solenoid to oppose the motion.

It is true that you will register no current. The reason is that the two magnets induce exactly opposing currents, which cancel.
 
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