A coil with turns given magnetic field, time find the emf induced in the coil

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A coil with 240 turns and an area of 13.7 cm² is rotated from perpendicular to parallel with the Earth's magnetic field of 5.9×10−5 T over 3.70×10^-2 s. The total magnetic flux through the coil before rotation is calculated as 1.9×10^-5 WB, while after rotation it is 0 WB. The average emf induced in the coil is being calculated incorrectly; the correct formula is emf = -N * B * A / T. Users suggest re-evaluating the area conversion from cm² to m² and ensuring proper division by the time interval. Accurate calculations are essential for determining the correct induced emf.
sonrie
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A coil with 240 turns enclosing an area of 13.7 cm^2 is rotated in a time interval of 3.70×10^-2 s from a position where its plane is perpendicular to the Earth's magnetic field to one where its plane is parallel to the field. The Earth's magnetic field at the lab location is 5.9×10−5 T .

What is the total magnetic flux through the coil before it is rotated?
I found this answer its 1.9*10^-5 WB.

What is the total magnetic flux through the coil after it is rotated?
I found this answer its 0 WB.

What is the average emf induced in the coil?

I'm having trouble getting the right answer! I get 1.27*10^-7 but its wrong! Help Please!
 
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sonrie said:
What is the total magnetic flux through the coil before it is rotated?
I found this answer its 1.9*10^-5 WB.
Double check the exponents in this answer.

What is the total magnetic flux through the coil after it is rotated?
I found this answer its 0 WB.
Good.

What is the average emf induced in the coil?

I'm having trouble getting the right answer! I get 1.27*10^-7 but its wrong!
How did you get this?
 
the equation is emf = -N BA/T

-240 5.9*10^-5*.137/5.9*10^-5=3.28*10^-9 its still wrong
 
sonrie said:
the equation is emf = -N BA/T

-240 5.9*10^-5*.137/5.9*10^-5=3.28*10^-9 its still wrong
You have the correct formula, but you need to redo the calculation more carefully:
(1) You have the incorrect area. (Note that 1 cm^2 = 10^{-4} m^2.)
(2) Divide by the time interval.
 
Thank you!
 

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