Power dissipation of 2 diodes (1 is a Zener diode)

[Edy56]

Homework Statement

The circuit in Figure 4 uses two diodes, D1 and D2. Write which diodes are in question. Determine the value of the power dissipated on diode D1. It is known: R1= 330 Ω, R2= 1 kΩ, V1= 9 V, VZ= 5, 6 V

Relevant Equations

None

Are my equations correct? And my process of how I should solved this problem?

 

[Gordianus]

Have you checked whether the zener diode is conducting?

 

[Edy56]

Have you checked whether the zener diode is conducting?

Zener Is because it requires 5.6 volts and sicillium one always does.

 

[Gordianus]

Thus, if you feel confident, compute the currents and node voltages.

 

[Baluncore]

Zener Is because it requires 5.6 volts and sicillium one always does.

5v6 is the Zener breakdown voltage only for that 5v6 Zener diode, which is not always the operating voltage. It could be less.
The resistors R1 and R2, with D2, form a potential divider. It is possible that the Zener diode, D1, has a voltage below 5.6 volts, and so does not conduct. Check that first.

Once you have determined the actual voltage on D1, you can solve for the current and power in D2.

Solve for the current through R1, subtract the current that flows through R2 and D2. What current remains flows through D1.

 

[berkeman]

It's hard to read your handwriting. Is $V_1 = 5V$ or is $V_1 = gV$?

 

[Babadag]

From the sketch above it looks to me like the Zener is reverse biased so the voltage after the R1 is constant 5.6V. And so you may calculate I.
Subtract 0.7 volts - the voltage drop constant across D2 - from 5.6 V and then calculate I2

 

[vela]

It's hard to read your handwriting. Is $V_1 = 5V$ or is $V_1 = gV$?

I'd guess it's $V_1 = 9~\rm V$.

Are my equations correct? And my process of how I should solved this problem?

I'd say no. You've written things like $V_1 = R_1$ and $V_2=5.6~\rm V$ and $V_2=0.7~\rm V$ (hence implying 5.6=0.7!). Plus you don't appear to indicate exactly what you mean by $V_2$ as far as I can see.

ETA: Oh, I see! Some of those 2s are actually Zs. There's a reason we ask you to type up your work. Your handwriting isn't as easy to read as you might think.

It would be more helpful if you explain your thought process behind your work instead of spewing a bunch of equations and asking "are they right?" That way the helpers can see where you're getting stuck and possibly help you identify what you're unsure about.