some body help me please

WBahn

Joined Mar 31, 2012
30,058
We can help you AFTER you show YOUR attempt to solve it. That will let us get a glimpse of what approach you are trying and where you are going right and where you are going wrong.

The bad news is that I suspect they were expecting you to be able to answer this question immediately and by inspection. But just telling you the answer won't help you learn the concepts that they wanted to know if you knew. So let's take it one step at a time.

In terms of the variables Vs, R1, R2, and RL, where Vs is the 100V supply and RL is the 50Ω load resistor, what is the power that is delivered to RL? Let's get that far and, once that is correct, we can proceed.
 

shteii01

Joined Feb 19, 2010
4,644
You have four combinations of R1 and R2.

Case 1.
R1=0
R2=0
Assuming 50 Ohm is the load, solve for power.

Case 2.
R1=0
R2=100 Ohm
Assuming 50 Ohm is the load, solve for power.

Case 3.
R1=100 Ohm
R2=0
Assuming 50 Ohm is the load, solve for power.

Case 4.
R1=100 Ohm
R2=100 Ohm
Assuming 50 Ohm is the load, solve for power.
 

WBahn

Joined Mar 31, 2012
30,058
The problem doesn't say that R1 and R2 are either 0Ω or 100Ω, it says that that are merely between those two values, inclusive, and he is supposed to find values that result in the maximum power possible delivered to the load.

At least that's the way I read the problem description.
 

shteii01

Joined Feb 19, 2010
4,644
The problem doesn't say that R1 and R2 are either 0Ω or 100Ω, it says that that are merely between those two values, inclusive, and he is supposed to find values that result in the maximum power possible delivered to the load.

At least that's the way I read the problem description.
It is actually pretty simple.

When R1=0 (R1 is short), 100 volts is across the load, that is when there is maximum power at the load.

Or you can crunch the numbers. "Pilot's choice."
 

Thread Starter

qwertyuiopoiuytrewq

Joined Oct 10, 2014
16
We can help you AFTER you show YOUR attempt to solve it. That will let us get a glimpse of what approach you are trying and where you are going right and where you are going wrong.

The bad news is that I suspect they were expecting you to be able to answer this question immediately and by inspection. But just telling you the answer won't help you learn the concepts that they wanted to know if you knew. So let's take it one step at a time.

In terms of the variables Vs, R1, R2, and RL, where Vs is the 100V supply and RL is the 50Ω load resistor, what is the power that is delivered to RL? Let's get that far and, once that is correct, we can proceed.
I tried to solve using thevenins theorem & maximum power transfer theorem but i failed to solve.Could you please help me.
 

t_n_k

Joined Mar 6, 2009
5,455
This could get laborious.
Perhaps the OP should read post #9. Almost the end of the story .... except for a statement concerning R2.....
 

WBahn

Joined Mar 31, 2012
30,058
I tried to solve using thevenins theorem & maximum power transfer theorem but i failed to solve.Could you please help me.
Then SHOW us your attempt to solve it that way. Go back and try using the approach I suggested in Post #5. You've been given plenty of hints that should lead you to see the solution by inspection, but the fact that you aren't seeing how to exploit them is a strong indicator that you will be best served by slugging through it. At some point you will have an, "Ah hah!" moment and see the light.
 
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