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**1. Homework Statement**

A 22.0-cm-diameter coil consists of 20 turns of circular copper wire of 2.6 mm in diameter. A uniform magnetic field, perpendicular to the plane of the coil, changes at a rate of 8.65 x 10

^{-3}T/s. Determine (a) the current in the loop, and (b) the rate at which thermal energy is produced.

**2. Homework Equations**

V = NBA / t

R= pl/A

l = N*2*pi*diameter of coil

A = pi*(radius of wire)

^{2}

I = V/R

**3. The Attempt at a Solution**

I understand the part (a)... sort of. Tell me if I did it something wrong.

V = NBA / t

V = (20)(8.65 x 10

^{-3}T/s)(pi*(.0013 m)

^{2}) = 9.19 x 10

^{-3}V

R = pl/A

R = (1.72 x 10

^{-8})(20*2*pi*.22 m)/ (pi*(.0013 m)

^{2}) = 8.96 x 10

^{-2}ohms

I = V/R

I = 9.19 x 10

^{-3}V / 8.96 x 10

^{-2}ohms = 1.03 x 10

^{-5}A

Part (b) I don't understand. I don't know what I'm finding.