diff --git a/Data_Structures/Patterns/Factory_pattern.md b/Data_Structures/Patterns/Factory_pattern.md
index 87c5e69..9f4619b 100644
--- a/Data_Structures/Patterns/Factory_pattern.md
+++ b/Data_Structures/Patterns/Factory_pattern.md
@@ -1,6 +1,6 @@
 ---
 tags:
-  - Data_Structures
+  - Data Structures
   - patterns
   - oop
 ---
diff --git a/Electronics/Physics_of_electricity/Coulombs_Law.md b/Electronics/Physics_of_electricity/Coulombs_Law.md
index e69de29..1ef284b 100644
--- a/Electronics/Physics_of_electricity/Coulombs_Law.md
+++ b/Electronics/Physics_of_electricity/Coulombs_Law.md
@@ -0,0 +1,17 @@
+---
+categories:
+  - Electronics
+tags: [physics, electricity]
+---
+
+# Coulombs Laws 
+
+Coulomb's Laws express the fundamental relationship between charge, force and attraction. They are also known as the **Electrostatic Laws**.
+
+## First Law 
+
+> Like charges of electricity repel each other. Unlike charges attract each other. 
+
+Within the atom we see this at work in the way that negatively charged electrons are attracted to the positively charged nucleus. This attractive force is balanced by the centrifugal force caused by the electron's rotation around the nucleus. This keeps the electrons in orbit. Without it, they would spiral into the nucleus. 
+
+Within circuits, the first law dictates the movement of charge from negatively charged atoms to positively charged atoms through the conductor. 
\ No newline at end of file
diff --git a/Electronics/Physics_of_electricity/Current.md b/Electronics/Physics_of_electricity/Current.md
index 077b35d..9f51042 100644
--- a/Electronics/Physics_of_electricity/Current.md
+++ b/Electronics/Physics_of_electricity/Current.md
@@ -14,9 +14,38 @@ So current is the flow of electrons. Charge is the quantity that flows. Current
 
 We use the symbol $I$ to stand for current in equations. 
 
+## Why current exists
+Current exists because of the [first law of electrostatics](/Electronics/Physics_of_electricity/Coulombs_Law.md).
 
-## Coulombs and amps
+When there is an excess of electrons at one terminal (i.e. negatively charged atoms) and a deficiency of electrons at the other terminal (i.e. positively charged atoms), a difference of potential exists between the two terminals.
 
-We measure **charge** in Coulombs ($C$). A Coulomb is an aggregate of the charge of several electrons because their individual charge is so small: $6.24 \cdot 10 ^{18}$ electrons. 
+When the terminal are connected to each other via a conductor (e.g. copper wire) electrons will flow along the conductor. This is provided that there is a source to supply electrons at one end and remove them at the other. This is **voltage source**.
+
+_The diagram below illustrates the flow of current where the circles are electrons knocking into each other to generate current:_
+
+![](/img/charge-cylinder.svg)
+
+## Formal expression
+
+We measure **charge** in Coulombs ($C$). A Coulomb is an aggregate of the charge of thousands of electrons because their individual charge is so small.
+One Coulomb is equal to the charge of $6.24 \cdot 10 ^{18}$ electrons. 
 
 We measure **current** in amps. When one coulomb of charge moves past a point in one second it is called an **ampere** (amp) represented as $A$. 
+
+This relationship is captured in the following equation:
+
+$$
+I = \frac{Q}{t}
+$$
+
+* $I$ = current measured in amps
+* $Q$ = quantity of electrical charge measured in coulombs
+* $t$ = time
+
+### Application
+_Calculate the current in amps if 9 coulombs of charge flow past a point in an electric circuit in 3 seconds._
+
+$$
+I = \frac{9}{3} \\
+I = 3  A
+$$
\ No newline at end of file
diff --git a/Electronics/Physics_of_electricity/Electrons.md b/Electronics/Physics_of_electricity/Electrons.md
index eedfd73..5d77970 100644
--- a/Electronics/Physics_of_electricity/Electrons.md
+++ b/Electronics/Physics_of_electricity/Electrons.md
@@ -12,6 +12,8 @@ Electrons orbit in concentric circuits around the nucleus of the atom. Each orbi
 
 Each shell can accomodate a maximum number of electrons. The shells are designated letters and filled in sequence moving out from the shell nearest to the nucleus. 
 
+_The diagram below demonstrates shell naming conventions and the maximum number of electrons per shell._
+
 ![](/img/electron-shells.svg.svg)
 
 ## Valence