A
Active8
- Jan 1, 1970
- 0
No, the direction of the induced EMF is such as to oppose the change of
current that produced it, hence:
V = -L di/dt
As you say, di/dt is negative, hence the induced voltage is positive,
Hmmm. Difference between voltage drop and counter EMF. Let's see how
many screw ups I can find.
I see Haliday and Resnick managed to foul things up by first writing
lineIntegral [ E.dl ] = -d_phi/dt
and then in the chapter on Maxwell they drop the negative sign and
reference the above eq as if they didn't change it. That's Table
37-1 with no mention of why it's dropped. In Table 37-2 the put it
back and never mention why but they discuss adding a missing term to
Ampere's Law from a prior chapter.
No where else to look for screw ups. Oh well, at least I remember
which way the protection diode goes.