Experiment No.2 Diodes n LED

 Diode is a semiconductor that normally allows electricity to flow in only one way. 

 There are many types of diodes such as rectifying diodes( the normal one); Zener; LED....

But all are constructed based on a basic structure of boundary layers of Positive and negative.

 

 Fairly to say, I don't have to try to break the concept of  "diode" to bare ground, but most importantly how to wire it in a circuit. Anode is positive, Cathode is negative, and as we consider Conventional Current flows from positive to negative, hence when we wire the diode, we put anode to the input, and cathode to where we want the electricity to flow. If we don't want electricity to flow through, just do the reverse.

LED- Light Emitting Diode is exactly the basic diode but it allows us to see whether it works or not., n of course, it lights when forward biased.

In our practical assignment: we have to test a diode and a LED, using a multimeter set to Diode test mode: There is 2 things we need to find: Voltage drop in forward n reverse bias. Needless to say, of course VD in reverse will be Over Limit, because the diodes won't allow any current through, if Voltage applied through them is too big, it will break through the boundary layer hence destroy the function of the diode. 

But why forward VD of LED is 1.78V and Diode is 0.57V? Because these are the specification for these 2 diodes in order to push through the boundary layer, even if it's little.