How Do You Calculate Thevenin Equivalent Circuit Without a Load Resistor?

[Alexander Max]

Homework Statement

I am to find the thevenin equivalent circuit without the load resistor (to the left of terminals a &b

Homework Equations

From class notes:
1- Remove the load resistor
2- find the open circuit voltage across a & b
3- Remove all voltage sources (replace with short circuit)
4- Detrmine the equivalent circuit resistance across the break
5- Form an equivalent circuit

The Attempt at a Solution

I have not come across the symbol that looks like an 8 with the 2amps next to it so far, and i don't understand how this will effect my circuit, is it a voltage source, how will it effect the resistors?
Without acknowledging it,
my resistors are all in parralel so Restance total is
1/RT = 1/R1 + 1/R2 + 1/R3
1/RT = 1/4 + 1/12 + 1/1
1/RT = 3/12 + 1/12 + 12/12
1/RT = 16/12
RT = 12/16
RT = 0.75

32v/0.75 ohms = 42.667 Amps
Vab = 32 - 1x42.667Amps = -10.667 Volts

Resistance looking in has already been calulated as 0.75 ohms

 

[BvU]

Hello Alex, and welcome to PF :)

The 2A thingy is a (slightly outdated) symbol for a current source.

I don't see how you can consider all R as parallel.

 

[gneill]

Hi Alexander Max, Welcome to Physics Forums.

As BvU stated, the two-circle symbol represents a current source. It's a bit outmoded as a schematic symbol, but it still crops up fairly often.

Allow me to amend your algorithm's item 3 a bit, since in its given form it doesn't address current sources:

3 - Suppress all independent sources: Replace voltage sources with a short circuit and all current sources with an open circuit (simply remove them entirely).

 

[Alexander Max]

Thank you for your help!