Question

reason for negative sign of self inductance​

Answer 1

Answer:

Since self-inductance is associated with the magnetic field produced by a current, any configuration of conductors possesses self-inductance. ... In accordance with Lenz's law, the negative sign in (Figure) indicates that the induced emf across an inductor always has a polarity that opposes the change in the current.

Answer 2

this is the reason for negative sign of self inductance