A 20 H inductor carries a steady current of 4.0 A. At what rate must the current be changed to produce a 40 V emf in the inductor?(adsbygoogle = window.adsbygoogle || []).push({});

I odn't get this one because it gives you all the information!!

The formula is:

EMF = -L di/dt

they want u to find di/dt, but they already give you it has a steady current of 4.0A, so isn't di/dt just i, which is 4.0A?

Then the EMF would be 40, and they say L = 20H, so i'm stuck on what intermediate step i'm missing! thanks

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# Homework Help: At what rate must the current be to changed to produce 40V emf

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