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fredrick08
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Homework Statement
The magnetic field at one place on the earth’s surface is 55 μT in strength and tilted 60°
down from horizontal. A 200-turn coil having a diameter of 4.0 cm and a resistance of 2.0 Ω
is connected to a 1.0 μF capacitor rather than to a current meter. The coil is held in a
horizontal plane and the capacitor is discharged. The coil is then quickly rotated 180° so that
the side that had been facing up is now facing down. Afterward, what is the voltage across
the capacitor? [Hint: use I=dq/dt
Homework Equations
[tex]\Phi[/tex]=ABcos[tex]\theta[/tex]
Vc=Q/C
Vl=-L(di/dt)
Vc=-Vl
I=[tex]\Phi[/tex]/L
[tex]\Phi[/tex]=N[tex]\Phi[/tex]per coil
The Attempt at a Solution
ok wat i did was find flux per coil=[tex]\pi[/tex]r2Bcos[tex]\theta[/tex]=3.45x10-8
then flux=3.45x10-8*200=6.9x10-6=L(di/dt)=Q/C...
but that can't be right coz i know the answer is 12V... can someone please help me, I've been on this for 4 or hours and its 3am almost... due in tomoz... please someone help...