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gneill
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Andrew187 said:I2 = 0.81a?
Yes. Carry on,... what's the Thevenin resistance?
Andrew187 said:I2 = 0.81a?
gneill said:Yes. Carry on,... what's the Thevenin resistance?
Andrew187 said:7.032v/0.81a=8.68 ohm ?
gneill said:Yes. Carry on... draw the Thevenin equivalent circuit with the load RL attached. What value of RL maximizes the power transfer (Max Power theorem).
Andrew187 said:That bits not the problem I don't know how I worked out the value for I1 and how I got Isc to 0.81a
gneill said:yes, and so,...
Andrew187 said:Isc=
(9+25)*i1 - 25*i2 = 15
-25*i1 + (25+7)*i2 = 0
This Is the bit I didn't understand i took this out of my notes I know here that the value of I2=0.293a, but I didn't quite understand how I worked out I1.
gneill said:Can you be more specific about what you don't understand? You have written two equations in two unknowns, which can be solved using whatever technique you're familiar with. What part is stumping you?
1. Writing the equations from the circuit.
2. Solving two equations for two unknowns.
Andrew187 said:Writing it shouldn't be a problem but solving the two equations from the two unknowns is a problem I know the answer but don't know how I solved it.
gneill said:Then it sounds like you need to review your algebra and simultaneous equation solving. This is a fundamental skill that you must have in order to solve problems in any technical discipline. A web search on "solving simultaneous equations" will turn up some on-line tutorials.
Andrew187 said:Sorry what I was meant to say was solving the equation isn't really the problem because I can sit till the cow's come home calculating the unknowns I eventually get there but the bit I struggle with is writing the equations and drawing the correct diagram, because when I try to look at notes and books its always done differrent to the way in which I want to achieve. So This is where I am at, I have found the value of RL I also know the unknowns but I 'm not sure what format and what diagrams to use bearing in mind I have used kirchhoffs and thevenins equivalent I think.
hussain bani said:i have tried to short both bateries for finding rth but i can't understand how to solve to find rth... can someone please help me finding rth..