How come when you reverse a diode the current/voltage? is zero?

In summary, the individual is having trouble understanding a concept related to diodes and has searched for an answer in their book and online. They are requesting assistance and have received suggestions to either not worry about it or to obtain the syllabus and confront their teacher. However, they are still seeking a simple explanation in English as they have not yet learned about P-N stuff.
  • #1
mmmboh
407
0
Hi I have been looking through my book, and even online for the answer because I don't understand why this happens, but I can't find the proper answer anywhere...can someone help me? Thanks.
 
Physics news on Phys.org
  • #3
ok you will never need to know why its is the case until you do it as a job or do it at uni you do whoever have to recognise the graph odd but true.(Uk only)
 
  • #4
Haha thanks but my teacher wants us to find out...and I read something like what wikipedia says but that is not the answer I'm suppose to have I already asked him :S.
 
  • #5
if you are in the Uk get a copy of the sylabus and wave it in his face saying you don't need to know it sorry its my only anser.
 
  • #6
Haha, no I'm not actually. I think he wants us to explain it in ENGLISH though, you know simply, because we haven't learned anything about P-N stuff yet...
 

1. How does a diode work?

A diode is a semiconductor device that allows current to flow in only one direction. It consists of a PN junction, where one side is doped with a certain type of material (P-type) and the other side is doped with a different type of material (N-type). When a voltage is applied in the forward direction, the majority charge carriers (electrons and holes) are able to flow through the diode, allowing current to pass. In the reverse direction, the majority charge carriers are blocked by the PN junction, resulting in no current flow.

2. Why is current zero when a diode is reversed?

When a diode is reversed, the majority charge carriers are blocked by the PN junction. This means that there are no carriers available to conduct current, resulting in a net current of zero.

3. Can current still flow in the reverse direction?

In theory, some current can still flow in the reverse direction due to minority charge carriers (electrons in the P-type material and holes in the N-type material) that are able to cross the PN junction. However, this current is very small and is typically ignored in circuit analysis.

4. What happens if a diode is connected in reverse bias?

If a diode is connected in reverse bias, meaning the positive terminal of a power source is connected to the N-type material and the negative terminal is connected to the P-type material, it will not conduct current. In fact, if the reverse bias voltage exceeds a certain threshold, called the breakdown voltage, it can cause the diode to breakdown and conduct current in the reverse direction.

5. Why does a diode have a high resistance in the reverse direction?

In the reverse direction, a diode behaves like an open circuit, meaning it has a very high resistance. This is because the PN junction acts as an insulator, preventing current from flowing through the diode. As a result, the diode can be used as a switch to control the flow of current in a circuit.

Similar threads

  • Introductory Physics Homework Help
Replies
3
Views
235
  • Introductory Physics Homework Help
Replies
26
Views
3K
  • Introductory Physics Homework Help
Replies
6
Views
985
  • Introductory Physics Homework Help
Replies
13
Views
2K
  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
1K
  • Introductory Physics Homework Help
Replies
12
Views
7K
  • Introductory Physics Homework Help
Replies
7
Views
2K
  • Introductory Physics Homework Help
Replies
8
Views
233
Back
Top