Steven W. answered • 08/15/16
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Hi Vikram!
This problem seems to be set up to use Faraday's law, which relates induced emf (voltage) to changing magnetic flux:
emf = -N((ΔΦB)/Δt)
However, I think a few aspects need to be clarified to be able to complete this calculation:
1. We need to have some kind of value(s) that allow(s) us to calculate the magnetic field strength, and some way to determine how its strength changes as the magnet moves at 4 cm/s (which I assume is an average speed over one pass through the coil). I assume the field gets stronger with time as the magnet approaches, and weaker as it goes away, but we need to be able to assign a value to that change to figure out the change in flux and calculate the induced emf in the coils.
2. I assume "how much electricity" refers to the strength of generated current. However, Faraday's law calculates induced emf or voltage. To compute the current in the coils, we would have to know the resistance of the coil (either resistance per turn over overall resistance will do). We could also use the resistivity of the wire material, as long as we knew something about the radius of the coil.
If you can provide more information about the strength of the field (and how it changes as the magnet approaches or recedes) and about the resistance of the coil, I would be happy to help more!
Steven W.
tutor
Hi Vikram!
Unfortunately, the strength of the magnetic field from the magnet is a vital quantity to know to determine the induced voltage, which can then be combined with a knowledge of coil resistance to determine the induced current. The mass of the magnet and coil are not particularly useful here. We need to know the rate at which the magnetic field penetrating the area of the coils in the loop is changing.
As the magnet approaches, the magnetic field strength increases, and more field lines penetrate the loop. As it recedes, the opposite happens. Those changes in the amount of the magnetic field penetrating the loop are what determine the amount of induced voltage, and thus current. So we need a way to be able to know, or at least estimate, that. Knowing at least the average magnetic field strength (preferably in units of tesla (T), though we can convert from other units) is necessary for this calculation.
I do not have a way to post a diagram here, but if you search for "magnetic field through a coil" on the internet, you will find many pictures illustrating this situation.
Perhaps the average field strength is engraved on the magnet itself, or it can be looked up? Or, if you can find a magnetometer to measure it (though, if you had that, you could probably get a multimeter and measure the current in the coil directly). But you have to be able to know that. In my opinion, there is no other direct way to calculate the electricity generated in this situation.
[NOTE: I suspect, though I cannot immediately work out, that the electric power you generate cannot exceed the power consumed by your 3 V toy motor; which I assume is powered by a current of some kind; otherwise, you would be making more energy out of less; so if you know the power your toy motor consumes, you could at least make an upper limit, I think, for the amount of electrical power you generate, which could be converted into an upper bound for current if we know the resistance of the coil]
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08/16/16
Vikram kumar G.
Dear Sir, Thankyou very much for you answer.
Sir, we can take very powerful magnet and if a weight of a magnet is 100 kilogram then it should be supposed that it is very powerful.
Sir,if you could your personal email address then I can send complete details regarding my Idea that how we can move a 100 kilogram weight magnet in linear motion.we can even move 1000 kilogram or more and more kilogram magnet with the help of this Idea.
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08/16/16
Vikram kumar G.
we will take magnetic strength of this magnet 30000 gauss .
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08/16/16
Steven W.
tutor
Thanks very much for the estimate of the magnetic field strength, since that is only partially determined by mass (the type of material matters just as much, and there are other factors). Is that a maximum strength for the field (closest to the magnet) or more of an average strength (since the field of a bar magnet is not typically uniform)?
This will all lead into the next aspect, then, is trying to estimate the change in flux.
I am not allowed to give personal email addresses on this site. We would need to set up an official online session. Just let me know if you would like to do that.
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08/16/16
Vikram kumar G.
I 'm very much interested to talk to you .
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08/16/16
Steven W.
tutor
Then we will have to go through WyzAnt, and treat it as an online lesson. I have a normal online rate... but this particular problem interests me, so that rate is negotiable. The next step, if you want to take it, is to send me a message, which will make it possible for us to set up a lesson. If you are unhappy with the first lesson, there is a "good-fit" guarantee from WyzAnt which would refund its cost to you, so there is little risk.
If you would like to proceed that way, just click on my link at the bottom of my entries above ("Steven W.") and send me a message. Then we can go from there. Sending the message, by the way, does not oblige you to make an appointment, so there is no commitment in just the message.
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08/16/16
Vikram kumar G.
Dear sir,
Thanks a lot for your response.
Sir, you please search ' vikram energy generation with magnetic repelling and gravity' where I've post my Idea .
Please review this Idea and guide me with your comments.
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08/16/16
Vikram kumar G.
08/16/16