Derive a formula for equivalent resistance

In summary, a formula for the equivalent resistance of n sections in cascade can be derived using the series and parallel equations. The equivalent resistance for n sections in series is Reqv = R1 + R2 +...Rn, while the equivalent resistance for n sections in parallel is Reqv = 1/{(1/R1) + (1/R2) + (1/R3) +...(1/Rn)}. To solve for the equivalent resistance of n sections in cascade, one would need to find the resistance of each individual stage and then apply the series and parallel equations accordingly. This can be done by considering the last resistor, Rn, as the last branch in any similar circuit, and then finding the equivalent resistance of
  • #1
boo_lufc
28
0
Is it possible to derive a formula for the equivalent resistance of n such sections in cascade?
Show your analysis.

Series: Reqv = R1 + R2 +...Rn

Parallel: Reqv = 1/{(1/R1) + (1/R2) + (1/R3) +...(1/Rn)}
 

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  • #2
boo_lufc said:
Is it possible to derive a formula for the equivalent resistance of n such sections in cascade?
Show your analysis.

Series: Reqv = R1 + R2 +...Rn

Parallel: Reqv = 1/{(1/R1) + (1/R2) + (1/R3) +...(1/Rn)}

...and how would you go about attempting to solve this? What is the resistance of one stage? And the resistance of two stages in series? And...
 
  • #3
I was thinking Rn is the last resistor so the last branch of any similar circuit would be
Rn + Rn-1 in series
Then this would be in parallel with Rn-2 + Rn-3 and so on
i.e Reqv = 1/ {(1/Rn + Rn-1) + (1/(Rn-2 + Rn-3) + (Rn-4 + Rn-5)}
Is this along the right lines at
 

Related to Derive a formula for equivalent resistance

1. What is equivalent resistance and why is it important?

Equivalent resistance is the total resistance of a circuit when multiple resistors are connected in series or parallel. It is important because it allows us to simplify complex circuits into a single equivalent resistor, making it easier to analyze and understand the overall behavior of the circuit.

2. How do you calculate equivalent resistance for resistors in series?

To calculate the equivalent resistance for resistors in series, simply add the individual resistances together. This is because the current flowing through each resistor is the same, and the total resistance is equal to the sum of all resistances in the circuit.

3. What is the formula for equivalent resistance in parallel?

The formula for equivalent resistance in parallel is 1/Req = 1/R1 + 1/R2 + ... + 1/Rn, where Req is the equivalent resistance and R1, R2, ..., Rn are the individual resistances. This formula takes into account that the current is divided between each resistor in a parallel circuit.

4. Can you use the formula for equivalent resistance for any type of circuit?

Yes, the formula for equivalent resistance can be used for any type of circuit, as long as the resistors are connected in either series or parallel. If the circuit contains a combination of series and parallel resistors, the equivalent resistance can be calculated by simplifying the circuit into smaller sections and then using the formula.

5. How is equivalent resistance useful in real-world applications?

Equivalent resistance is useful in real-world applications because it allows us to predict the behavior of a circuit and determine the amount of current that will flow through it. This is important in designing and troubleshooting circuits in various electronic devices such as computers, smartphones, and household appliances.

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