(adsbygoogle = window.adsbygoogle || []).push({}); A magnetic field with the time dependence shown in Figure 23-38 is at right angles to a181turn circular coil with a diameter of3.91 cm. What is the induced emf in the coil at each of the following times?

(a) t = 2.50 ms

0 V

(b) t = 7.50 ms

(c) t = 15.0 ms

0 V

(d) t = 25.0 ms

N = 181

A = .01955[tex]^2[/tex]

i've gotten (a) and (c) right but am having a very hard time with (b) and (d). for (b) i've been doing [tex]\phi[/tex] = BA cos [tex]\theta[/tex] where [tex]\theta[/tex] = 0 for t= 7.50 m/s as the final flux and then at t= 2.50 m/s for the initial flux . Then to find induced emf i've been doing 181(([tex]\phi_{f}[/tex] - [tex]\phi_{i}[/tex])/(7.50 - 2.50)) but am getting the wrong answer, what am i doing wrong??

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# Homework Help: Induced Emf in a coil

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