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Sorry
this is the first time i come to this forum.
Why the Ldi/dt in the left side is minus but not plus sign
i got confused
Does everyone can help me in this problem
thank you

i know VRiLdi/dt=0 is true in the right hand side
however,it doesnt make sense that the "L di/dt" term is still the same
when the di/dt is decreasing rather than increasing in the left hand side.
V=0
the direction of the induced emf is reverseing(so it should be Ldi/dt but not Ldi/dt?)
the Ri is still the same when the i is in the same direction as before.
i think it should be L*di/dtRi=0
what's wrong with that?
this is the first time i come to this forum.
Why the Ldi/dt in the left side is minus but not plus sign
i got confused
Does everyone can help me in this problem
thank you

i know VRiLdi/dt=0 is true in the right hand side
however,it doesnt make sense that the "L di/dt" term is still the same
when the di/dt is decreasing rather than increasing in the left hand side.
V=0
the direction of the induced emf is reverseing(so it should be Ldi/dt but not Ldi/dt?)
the Ri is still the same when the i is in the same direction as before.
i think it should be L*di/dtRi=0
what's wrong with that?
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