Thevinin analysis...

[i3ill]

Does anybody know the proper way to use thevinin analysis to find VTH and RTH for the followin circuit with R4 considered to be the load. What is the voltage across and current through the load?**broken link removed**

 

[ParkingLotLust]

Rth is found by opening R4 (load) and shorting V1. Simply calculate the value of R2 and R3 in parallel, then add the resistance of R1

Vth is found by using the voltage divider rule - 20v splis between R2 and R3, and Vth splits between R3 and R4

Then, use Ohm's Law to find the current through the load

We did this at the beginning of the year, so I apologise if Im a bit hazy

 

[Ubergeek63]

what's with the high school electronics question?

Same as anything else: open circuit voltage and source shorted source resistance.

 

[Roff]

Rth is found by opening R4 (load) and shorting V1. Simply calculate the value of R2 and R3 in parallel, then add the resistance of R1

No, Rth is R1, R2, and R3 in parallel.

Vth is found by using the voltage divider rule - 20v splis between R2 and R3, and Vth splits between R3 and R4

No, Vth is the voltage across R4 when R4 is open-circuit. Vth=V1(R2||R3)/(R1+(R2||R3))

Then, use Ohm's Law to find the current through the load

We did this at the beginning of the year, so I apologise if Im a bit hazy

 

[ParkingLotLust]

No, Rth is R1, R2, and R3 in parallel.

Completely missed that one

 

[Willbe]

I get Voc = ~3.9v and Isc = 2mA so Rth = 3.9/2=~2k.