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I'm not sure if I'm completely mistaken here, and I'm pretty sure I'm not..but here's the question info
In a physics laboratory experiment, a coil with 210 turns enclosing an area of 12.1cm2 is rotated in a time interval of 4.10×10−2s 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 6.1×10−5T .
1. What is the total magnetic flux through the coil before it's rotated?
I said that it should be 0 at this point because the plane of the area is perpendicular to the magnetic field.. (cos90 = 0), but they said the answer as if it were parallel, or I;m reading something wrong? got it, drew the picture wrong
2. What is it after rotating?
For this i thought there should be a value (from number 1), which i thought to be 1.54*10^-5, but the answer is 1.6*10^-5. I know i'm not off by much, but given that the numbers are quite specific I feel I might have done something wrong.
So was I right in thinking there was a mistake in this question? and do I calculate total flux by just doing number of coils times the BAcos?
One more thing >< what is the average emf induced in the coil?
Because the change in flux (-emf) is the previous value of flux divided by the given time, I got 3.9*10^-4, and again the answer is off by one digit. its 3.8*10^-4. And also I htought since we're lookin for average, I should be doing this answer + zero divided by 2..? but thats wrong
Thanks so much to someone who could help
In a physics laboratory experiment, a coil with 210 turns enclosing an area of 12.1cm2 is rotated in a time interval of 4.10×10−2s 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 6.1×10−5T .
I said that it should be 0 at this point because the plane of the area is perpendicular to the magnetic field.. (cos90 = 0), but they said the answer as if it were parallel, or I;m reading something wrong?
For this i thought there should be a value (from number 1), which i thought to be 1.54*10^-5, but the answer is 1.6*10^-5. I know i'm not off by much, but given that the numbers are quite specific I feel I might have done something wrong.
So was I right in thinking there was a mistake in this question? and do I calculate total flux by just doing number of coils times the BAcos?
One more thing >< what is the average emf induced in the coil?
Because the change in flux (-emf) is the previous value of flux divided by the given time, I got 3.9*10^-4, and again the answer is off by one digit. its 3.8*10^-4. And also I htought since we're lookin for average, I should be doing this answer + zero divided by 2..? but thats wrong
Thanks so much to someone who could help
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