Self Inductance—It is the property of a coil by the virtue of which it posses the growth or decay of induced current in a single coil.
Mathematically,
Magnetic flux changes in the coil is directly proportional to the induced current produced in the coil.
ϕ ∝ I ...(1)
ϕ = LI .....(2)
Where, L is a proportinality constant which is called self inductance.
L = ϕ/I ...(3)
Hence, co-efficient of self-inductance is the ratio of flux changes in the coil to the induced current produced in the coil.
If I = 1A ....(4)
L = ϕ .....(5)
Self Inductance of a single coil is numerically equal to flux changes in the coil, provided induced current provided in the coil is 1 ampere.
Using Faraday Second law,
Hence, self Inductance of a single coil is the ratio of induced emf produced in the coil to the ratio of loss of induced current with respect to time.
Therefore, self inductance of a simple coil is numerically equal to induced emf produced in the coil provided ratio of induced current with respect to time is 1AS–1.
