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PLEASE I NEED HELP I BEG YOU!!! PLSPLSPLSPLS ๐Ÿ™ (1 Viewer)

Gods_Spear

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I was solving this question:
1730852397079.png
to which they gave the folowing answer:
1730852436474.png
everything makes sense, I drew this graph, except mine was flipped around the x - axis. Is the falling magnet not creating a south pole at the top of the coil? Does this south pole not (using the right hand gripper coil rule) create a current flowing from the + to - terminal of the data prober, so why, FOR THE LOVE OF GOD, is it negative voltage first. Ive asked all my friends we're lost, so incredibly lost. Im begging, this shit will not leave my head if i dont get it out before the exam tomorow. Are we grosely misunderstanding something?? Im asking for your kind support ๐Ÿ™ ๐Ÿ™
 

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compd

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I was solving this question:
View attachment 45730
to which they gave the folowing answer:
View attachment 45732
everything makes sense, I drew this graph, except mine was flipped around the x - axis. Is the falling magnet not creating a south pole at the top of the coil? Does this south pole not (using the right hand gripper coil rule) create a current flowing from the + to - terminal of the data prober, so why, FOR THE LOVE OF GOD, is it negative voltage first. Ive asked all my friends we're lost, so incredibly lost. Im begging, this shit will not leave my head if i dont get it out before the exam tomorow. Are we grosely misunderstanding something?? Im asking for your kind support ๐Ÿ™ ๐Ÿ™
no. it's creating a north pole at the top to oppose change in flux.
 

sainzsgf

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it creates a north pole bc of lenz's law to oppose it
 

Gods_Spear

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Nah its creating a south pole surely, the south pole of the magnet is entering the coil, if it created a north pole it would attract the magnet in more.
 

sainzsgf

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North is at the top of the magnet, not the side entering the coil right?
no like the other end of the magnet will be south so the solenoid at the top becomes a north pole to attract the magnet
 

Gods_Spear

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no like the other end of the magnet will be south so the solenoid at the top becomes a north pole to attract the magnet
Why is the solenoid attracting the magnet? Doesnt the solendoids induced emf work to stop the force inducing it? Doesnt the solenoid want to repel the magnet?
 

Gods_Spear

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If the magnet was dropped North side in it makes sense, but its not, or am I being incredibly stupid? these induced emf questions are usually so easy
 

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Why is it creating a north pole?
When the north pole of the magnet approaches and passes through the solenoid, it induces an EMF in the coil due to Faraday's law of electromagnetic induction, which states that a changing magnetic field induces a voltage in a coil. The polarity of the induced voltage depends on the direction of the changing magnetic field and the orientation of the magnet. In this sense the orientation of the magnet would be considered north
 

Solarised

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The orientation of the north pole affects the initial direction of the induced voltage. The first positive peak corresponds to the north pole entering the solenoid, while the negative peak corresponds to the south pole exiting.
 

igor9

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it is creating a south pole, so there would be a north pole at the bottom initially. now use ur right hand grip rule or the solenoid rule and point ur thumb down. u will see ur fingers go in a clockwise direction ig. now if it goes in that direction, u will see the voltage firstly be negative on the data logger and then once it starts to exit the coil it will do the opposite, but i think the amplitude of the other part of the graph is greater coz probably the force of gravity acting on it is more, so the EMF generated would need to be greater to oppose this change of it now leaving the solenoid. idk this is what i think ๐Ÿ˜…
 

sainzsgf

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it is creating a south pole, so there would be a north pole at the bottom initially. now use ur right hand grip rule or the solenoid rule and point ur thumb down. u will see ur fingers go in a clockwise direction ig. now if it goes in that direction, u will see the voltage firstly be negative on the data logger and then once it starts to exit the coil it will do the opposite, but i think the amplitude of the other part of the graph is greater coz probably the force of gravity acting on it is more, so the EMF generated would need to be greater to oppose this change of it now leaving the solenoid. idk this is what i think ๐Ÿ˜…
you're probably correct, idk dont listen to me lmao
 

igor9

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you're probably correct, idk dont listen to me
lol idk this is the only stuff im alr at in the syllabus so hopefully im correct ๐Ÿ˜ฌ im so fucked for mod 7 and 8 rn ๐Ÿ˜ข
 

Gods_Spear

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When the north pole of the magnet approaches and passes through the solenoid, it induces an EMF in the coil due to Faraday's law of electromagnetic induction, which states that a changing magnetic field induces a voltage in a coil. The polarity of the induced voltage depends on the direction of the changing magnetic field and the orientation of the magnet. In this sense the orientation of the magnet would be considered north
I dont know about this tbh, other magnets in coil questions always consider the side entering first (ie the south pole of the magnet) before considering the back of the magnet. I mean Im wrong and your right so ill take your word for it but it seems very odd
 

Gods_Spear

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it is creating a south pole, so there would be a north pole at the bottom initially. now use ur right hand grip rule or the solenoid rule and point ur thumb down. u will see ur fingers go in a clockwise direction ig. now if it goes in that direction, u will see the voltage firstly be negative on the data logger and then once it starts to exit the coil it will do the opposite, but i think the amplitude of the other part of the graph is greater coz probably the force of gravity acting on it is more, so the EMF generated would need to be greater to oppose this change of it now leaving the solenoid. idk this is what i think ๐Ÿ˜…
Why would this lead to an initial negative spike?
 

Solarised

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I dont know about this tbh, other magnets in coil questions always consider the side entering first (ie the south pole of the magnet) before considering the back of the magnet. I mean Im wrong and your right so ill take your word for it but it seems very odd
You'll be fine in the test gl on it
 

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