(adsbygoogle = window.adsbygoogle || []).push({}); A conducting loop of wire has an area of 6.9 10-4 m2 and a resistance of 110[tex]\Omega[/tex] . Perpendicular to the plane of the loop is a magnetic field of strength 0.18 T. At what rate (in T/s) must this field change if the induced current in the loop is to be 0.18 A?

here's what i've done so far:

[tex]\theta[/tex] = 0

i used Ohm's Law V = IR to find V which is the same as EMF, which came out to be 19.8 V. Then to find initial flux i used [tex]\phi_{i}[/tex] = (.018T) (6.9 x 10[tex]^-4[/tex]) (cos 0) and got 1.242 x 10[tex]^-4[/tex]

this is where i think i might have gone wrong:

i'm assuming they are talking about a change over 1 second, so [tex]\Delta[/tex]t = 1s

and N = 1 since it originally says "A conducting loop of wire"

so i set up the Emf formula like this: 19.8 V = ([tex]\phi_{f}[/tex] - 1.242 x 10[tex]^-4[/tex]) and solved for [tex]\phi_{f}[/tex] and of course i'm not getting the right answer... any suggestions??

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# Homework Help: Rate of Magnetic Field Change

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