diff --git a/source/electronics/metrics.rst b/source/electronics/metrics.rst
index 209b499..a934413 100644
--- a/source/electronics/metrics.rst
+++ b/source/electronics/metrics.rst
@@ -50,7 +50,7 @@ A volt is the amount of energy per Coulomb (remember Coulomb
 is just a constant).
 
 .. math::
-	[V]=\frac{[J]}{C}=kg.m^2.s^{-2}.C^{-1}=kg.m^2.s^{-3}.C^{-1}.s=kg.m^2.s^{-3}.A^{-1}
+	[V]=\frac{[J]}{C}=kg.m^2.s^{-2}.C^{-1}=kg.m^2.s^{-3}.C^{-1}.s=kg.m^2.s^{-3}.[A]^{-1}
 
 Farad
 ^^^^^^^^
@@ -58,11 +58,11 @@ Components can hold electrons (such as capacitor).
 Farad defines the amount of Coulomb (electrons) retained by the component for each unit of voltage.
 
 .. math::
-	{[F]}=\frac{C}{[V]}=\frac{C}{kg.m^2.s^{-3}.A^{-1}}&=\frac{C}{kg.m^2.s^{-3}.C^{-1}.s}=\frac{C}{kg.m^2.s^{-2}.C^{-1}}
+	{[F]}=\frac{C}{[V]}=\frac{C}{kg.m^2.s^{-3}.[A]^{-1}}&=\frac{C}{kg.m^2.s^{-3}.C^{-1}.s}=\frac{C}{kg.m^2.s^{-2}.C^{-1}}
 
 	&=\frac{C^2}{[J]} =\frac{C^2}{[N].m} =\frac{s^2.C^2}{kg.m}
 
-	&=\frac{s^4.[A]^2}{kg.m}=m^{-2}.kg^{-1}.s^4.A^2
+	&=\frac{s^4.[A]^2}{kg.m}=m^{-2}.kg^{-1}.s^4.[A]^2
 
 Ohm
 ^^^^^^^
@@ -70,6 +70,12 @@ In circuits, components can resist to the current and thus reduces it.
 Ohm defines the amount of volts required at one end of the resistor to pass one ampere into it.
 
 .. math::
-	{[\Omega]}=\frac{[V]}{[A]}=\frac{kg.m^2.s^{-3}.A^{-1}}{[A]}=kg.m^2.s^{-3}.[A]^{-2}&=kg.m^2.s^{-3}.C^{-2}.s^{2}
+	{[\Omega]}=\frac{[V]}{[A]}=\frac{kg.m^2.s^{-3}.[A]^{-1}}{[A]}=kg.m^2.s^{-3}.[A]^{-2}&=kg.m^2.s^{-3}.C^{-2}.s^{2}
 
 	&=kg.m^2.s^{-1}.C^{-2}
+
+Henry
+^^^^^^^^^^
+
+.. math::
+   H=\Omega.s=\frac{kg.m^2.s^{-3}.[A]^{-1}}{[A]} \times s = \frac{m^2.kg}{s^2.[A]^2} = m^2.kg.s^{-2}.[A]^{-2}