couldnt the current go through it then through the resistor and to the negative terminal?

A wire is a component. The current cannot go through ANY component more than once.

 

A wire is a component. The current cannot go through ANY component more than once.

ohhh so D3,D2,D1 would ALL be reversed biased and have a zero current then?

 

ohhh so D3,D2,D1 would ALL be reversed biased and have a zero current then?

Correct.

At this point you should be able to figure out the answer.

To change the problem, reverse the polarity of D1, D2, and D3 and see if you can figure out what is going on in that case.

 

D4 has the most current and D1, D2 and D3 has the least at 0 current

if we reversed it then D1 and D4 would both have the same and most current
then would D2 D5 D6 have the same?
and D3 the least?

 

D4 has the most current and D1, D2 and D3 has the least at 0 current

Correct.

if we reversed it then D1 and D4 would both have the same and most current

Would they? Why?

Let's simplify it and remove the resistors in parallel with D2 and D3 and also remove D6. This would leave you with two parallel strings of diodes, one of which has two in series and one of which has three in series. Which string would have more current?

 

I figured that if it was reversed the current would flow equally to both D1 and D4 but I guess it would flow more towards D4?
I dont understand why this is though, the resistor is before both D1 and D4

 

I figured that if it was reversed the current would flow equally to both D1 and D4 but I guess it would flow more towards D4?
I dont understand why this is though, the resistor is before both D1 and D4

If the voltage difference between the top rail and the bottom rail is V0, what is the voltage across each diode in the string with two diodes and what is the voltage across each diode in the string with three diodes?

 

first the voltage would be the same for D1 and D4 would it not?

 

first the voltage would be the same for D1 and D4 would it not?

Why? Or, more to the point, how could it be the same?

You have three diodes that each drop some voltage (since the diodes are identical and they are carrying the same current -- since they are in series -- they each drop the same voltage). So the total voltage dropped across all three is just three times whatever voltage is dropped across one of them, right?

But the same reasoning holds for the parallel string that only has two diodes in it, meaning that the total voltage dropped across the string is just two times whatever voltage is dropped across one of these diodes, right?

But both string are in parallel which means that the voltage dropped across each string must total to the same value, right?

What does that mean about the voltage dropped across each diode in the first string (the one with three diodes) compared to the voltage dropped across each diode in the second string (the one with two diodes)?

 

well before we stated D5 and D6 were the same current, so I thought since D1 was revered now D1 and D4 would be the same. if there is 3 in series compared to 2 in series the 2 would get more voltage I would assume since there is less diodes in series

 

well before we stated D5 and D6 were the same current, so I thought since D1 was revered now D1 and D4 would be the same.

D5 and D6 have the same current by symmetry. They are identical diodes and have the same voltage across them because they are in parallel, so they have to have the same current though them. D1 and D4 are NOT in parallel (there is nothing forcing them to have the same voltage across them).

if there is 3 in series compared to 2 in series the 2 would get more voltage I would assume since there is less diodes in series

Correct. So D4 would have more voltage across it than D1. What does that mean about the currents?

 

D5 and D6 have the same current by symmetry. They are identical diodes and have the same voltage across them because they are in parallel, so they have to have the same current though them. D1 and D4 are NOT in parallel (there is nothing forcing them to have the same voltage across them).



Correct. So D4 would have more voltage across it than D1. What does that mean about the currents?

D4 also has more current than D1

 

D4 also has more current than D1

Correct.

But that's for this simplified circuit.

The case of the circuit with resistors and the other diode is more complicated. Reread my first (or second) post in this thread and see if that discussion now makes more sense.

 

You seem confused about how current flows.
Current flows from the positive battery terminal through any components that allow flow for that polarity and to the negative battery terminal.
Signal diodes do not generate current, they only control current based upon the polarity of the voltage applied to them.