- #1
Ylle
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Homework Statement
Hello...
I got a problem I really can't figure out.
I have the scenario in this link: http://www.gratisupload.dk/download/41677/"
Besides that I know that there is a magnetic field that works everywhere and is along the z-axis. This field, that depends on the y-coordinate and the time t is given as:
[tex]B=ky{{e}^{-{{t}^{2}}/{{\tau }^{2}}}}{{e}_{z}}$[/tex]
where tau is a positive time-constant, k is a constant with dimension T/m and ez is unit vector in the direction of the z-axis.
The magnetic field raises a magnetic flux through the circuit given by:
[tex]\[{{\Phi }_{B}}={{B}_{0}}{{L}^{2}}{{e}^{-{{t}^{2}}/{{\tau }^{2}}}}\][/tex]
where B0 is a positive constant with dimension T.
Now determine k
Homework Equations
[tex]\[{{\Phi }_{B}}=BA\][/tex]
The Attempt at a Solution
I know the answer is supposed to be:
[tex]\[k=2{{B}_{0}}/L\][/tex]
It seemed to good to be true if I just inserted the flux and the magnetic field into this equation, and then setting A = L2.
If I did that I got: k = B0 / y.
And I've been searching my book for examples and stuff I could use. But I can't come up with anything when I only have the magnetic field and magnetic flux. So I'm thinking there must be a trick that I'm not aware of :S
So can anyone point me in the right direction?Regards.
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