An aluminum ring of radius 5 cm and resistance 0.003 ohms is placed around the center of a long air-core solenoid with 1000 turns per meter and a smaller radius of 3 cm. If the current in the solenoid is increasing at a constant rate of 270 A/s, what is the induced current in the ring?(adsbygoogle = window.adsbygoogle || []).push({});

B= [tex] \mu*n*I [/tex]

change in B/change in time = [tex]\mu[/tex] n *change in current/change in time

= [tex] 4 \pi e-7)(1000)(270) [/tex] = .339

then change in flux/change in time= A*change in B/change in t

A= [tex] \pi*r^2 [/tex]

So A= (.03)^2 *3.14

then multiply that by .339 to get 9.58 e -4.

Then I divided this by 3 e -4 to get the current and found that it was 3.19..

which wasn't right.. can someone please help me? Thanks in advance!

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# Homework Help: Induced current

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