My teacher hasnt been in and Im trying to self teach this topic. Can

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To calculate the induced EMF in a flat circular coil with a mean diameter of 3.0 cm and 500 turns, use Faraday's law: EMF = -N(Δφ/Δt). The change in magnetic flux involves a transition from 20 mT to -20 mT over 60 ms. The area of the coil can be determined from its diameter, allowing for the calculation of magnetic flux. Additionally, when the EMF reaches its peak, the current is also at its peak, as per Ohm's law, which states that voltage is proportional to current.
KatieKangaroo
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My teacher hasnt been in and I am trying to self teach this topic. Can anyone help me with this question, its probably quite simple but I am really stuck :redface: :frown:
A flat circular coil of mean diameter 3.0cm has 500 turns and is situated so that the plane of the coil is perpendicular to a uniform magnetic field of flux density 20mT. The intensity of the field is reduced to zero and then increased to 20mT in the opposite direction at the same steady rate throughout. Calculate the EMF induced in the coil if the whole operation takes 60ms.
Thanks in advance for any help.

Also: if the EMF is at its peak, is the current also at its peak?
 
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KatieKangaroo said:
My teacher hasnt been in and I am trying to self teach this topic. Can anyone help me with this question, its probably quite simple but I am really stuck :redface: :frown:
A flat circular coil of mean diameter 3.0cm has 500 turns and is situated so that the plane of the coil is perpendicular to a uniform magnetic field of flux density 20mT. The intensity of the field is reduced to zero and then increased to 20mT in the opposite direction at the same steady rate throughout. Calculate the EMF induced in the coil if the whole operation takes 60ms.
Just use Faraday's law:

EMF = -N\frac{\Delta\phi}{\Delta t}

You have the magnetic flux density, so flux = density * area. You know the change in magnetic flux (+20mT to -20mT) and you know how long it took (60 ms). N is the number of coils.

KatieKangaroo said:
Also: if the EMF is at its peak, is the current also at its peak?
Ohm's law is V = iR, so yes: voltage (EMF) is proportional to current.
 
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