Question

The 4.00 A current through a 7.50 mH inductor is switched off in 8.33 ms. What is the emf induced opposing this?

Final Answer

$3.60 \textrm{ V}$

Solution Video

#### Sign up to view this solution video!

View sample solution## Calculator Screenshots

Video Transcript

This is College Physics Answers with Shaun Dychko. The induced EMF will equal the self-inductance times the rate of change of current and so that’s seven and a half milli-henry times change in four amps because we are told that it switched off and so its going from four to zero, so the change is four amps and it takes 8.33 milli-seconds for this change to happen and so we have 8.33 ten to the minus three seconds there and this means the induced EMF will be 3.6 volts.