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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Physics => Topic started by: dream chaser on September 25, 2019, 11:45:03 am

Title: Magnetic Flux Question
Post by: dream chaser on September 25, 2019, 11:45:03 am

Hi Guys,

Just a quick question. Does the number of turns affect the amount of magnetic flux? I know the VCE Physics formula sheet has flux = B x A, but if there is more than one turn in the alternator, can flux = N x B x A where N= number of turns?

So if a question asks you to find the average emf in the coil, when finding the change in flux, will I just make flux= B x A. Then when I use the average emf formula, then I put N=10 of what ever as EMF = =N x (change in flux/ change in time)?

All replies will be much appreciated. Thanks  :)

Title: Re: Magnetic Flux Question
Post by: Just another student on October 08, 2019, 02:44:10 pm

Quote from: dream chaser on September 25, 2019, 11:45:03 am

Hi Guys,

Just a quick question. Does the number of turns affect the amount of magnetic flux? I know the VCE Physics formula sheet has flux = B x A, but if there is more than one turn in the alternator, can flux = N x B x A where N= number of turns?

So if a question asks you to find the average emf in the coil, when finding the change in flux, will I just make flux= B x A. Then when I use the average emf formula, then I put N=10 of what ever as EMF = =N x (change in flux/ change in time)?

All replies will be much appreciated. Thanks  :)

I think the process you described is correct, but someone feel free to correct me.
So I think number of turns doesn't affect the magnetic flux but does affect EMF

Title: Re: Magnetic Flux Question
Post by: Erutepa on October 08, 2019, 05:18:30 pm

Quote from: dream chaser on September 25, 2019, 11:45:03 am

Hi Guys,

Just a quick question. Does the number of turns affect the amount of magnetic flux? I know the VCE Physics formula sheet has flux = B x A, but if there is more than one turn in the alternator, can flux = N x B x A where N= number of turns?

So if a question asks you to find the average emf in the coil, when finding the change in flux, will I just make flux= B x A. Then when I use the average emf formula, then I put N=10 of what ever as EMF = =N x (change in flux/ change in time)?

All replies will be much appreciated. Thanks  :)

Thats right! Flux really is a measurement of how much feild is passing through an area - so the number of turns does not change the amount of field passing through the area made by the coil.
And yes, you are right about the formula for calculating the emf induced in a coil (faraday's law) - I think it was a typo, but note that N has a negative coefficient.