(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A circular loop made from a flexible, conducting wire is shrinking. Its radius as a function of time is . The loop is perpendicular to a steady, uniform magnetic field B .

Find an expression for the induced ε in the loop at time t.

Give your answer in terms of , , t, B and appropriate constants.

2. Relevant equations

Magnetic Flux (Φm)=A*B

I(induced) = ε / R

ε =Absolute value of (dΦ/dt)

3. The attempt at a solution

At first get the magnetic flux using the Area * Magnetic field. Area is (pi)r^2 * B. I use this in faradays law with dt but i dont get the write expression. I end up getting

ε(t)=(B(pi)(r_0*e^(beta*t))^2)/t

I know im differentiating somewhere wrong but i dont know where.

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# Homework Help: Expression for induced ε from reducing Loop

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