Hello.
I am studying electronics and I came across a question that I am not able to resolve.
The question asks for the value of resistance R so that the 5 Ω resistor (R5) in the circuit is subjected to a potential difference of 5 V. The circuit mentioned is in the following figure.
I really tried a lot but I couldn't find a solution.
I redraw the circuit that looks like the figure below and I see that it looks like a wheatstone bridge. The wheatstone bridge is easy to solve if there is balance, which is not the case.
I tried it first by applying Kirchhoff's Current Law:
\( (A): I_4 = I_1  I_g \)
\( (B): I_3 = I_2 + I_g \)
From equations A and B and going through branches 1 and 2 (Kirchhoff's Voltage Law), we have:
\( (1): 20\cdot I_1  10\cdot I_2 + 20\cdot I_g = 0 \)
\( (2): 5\cdot I_4  20\cdot I_g + R\cdot I_3 = 0 \)
Knowing that:
\( I_4 = 1 A \)
and that:
\( I_3 = I_2 + I_g \)
Substituting in equations (1) and (2) we have:
\( (1): 20\cdot (1 + I_g)  10\cdot I_2 + 20\cdot I_g = 0 \)
\( (1): 40\cdot I_g  10\cdot I_2 + 20 = 0 \)
\( (2): 5  20\cdot I_g + R\cdot (I_2 + I_g) = 0 \)
And this is my limit. Try as I might, I can't get past this point.
That's why I came here to ask for help.
Does anyone have an idea how to resolve this question?
How to find the value of R so that the potential difference across resistor R5 is equal to 5 V?
Thanks for any help.
I am studying electronics and I came across a question that I am not able to resolve.
The question asks for the value of resistance R so that the 5 Ω resistor (R5) in the circuit is subjected to a potential difference of 5 V. The circuit mentioned is in the following figure.
I really tried a lot but I couldn't find a solution.
I redraw the circuit that looks like the figure below and I see that it looks like a wheatstone bridge. The wheatstone bridge is easy to solve if there is balance, which is not the case.
I tried it first by applying Kirchhoff's Current Law:
\( (A): I_4 = I_1  I_g \)
\( (B): I_3 = I_2 + I_g \)
From equations A and B and going through branches 1 and 2 (Kirchhoff's Voltage Law), we have:
\( (1): 20\cdot I_1  10\cdot I_2 + 20\cdot I_g = 0 \)
\( (2): 5\cdot I_4  20\cdot I_g + R\cdot I_3 = 0 \)
Knowing that:
\( I_4 = 1 A \)
and that:
\( I_3 = I_2 + I_g \)
Substituting in equations (1) and (2) we have:
\( (1): 20\cdot (1 + I_g)  10\cdot I_2 + 20\cdot I_g = 0 \)
\( (1): 40\cdot I_g  10\cdot I_2 + 20 = 0 \)
\( (2): 5  20\cdot I_g + R\cdot (I_2 + I_g) = 0 \)
And this is my limit. Try as I might, I can't get past this point.
That's why I came here to ask for help.
Does anyone have an idea how to resolve this question?
How to find the value of R so that the potential difference across resistor R5 is equal to 5 V?
Thanks for any help.
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