Calculate Unknown Resistance in Parallel Circuit

Thread starter Bryster77
Start date Mar 25, 2009
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Circuits Parallel

AI Thread Summary

To find the unknown resistance in a parallel circuit with a 3.3-ohm resistor and another resistor across a 3V battery, the total current is 1.41 A. The formula used is R = (1/(1/3.3 + 1/x))^-1, leading to the equation 3V = 1.41A(R), which simplifies to R = 2.13 ohms. To solve for the unknown resistance x, the equation 2.13 ohm = (1/3.3 ohm + 1/x ohm)^-1 is applied. The final calculated value for x is 6 ohms. The discussion highlights the process of using Ohm's Law and parallel resistance formulas to find unknown values in electrical circuits.

Mar 25, 2009

Bryster77

a 3.3ohm resistor and another resistor are connected in parallel across a 3v battery. the current in the circuit is 1.41 A. Find the uknown resistance

R=(1/3.3 + 1/x)^-1

V=IR
3v= 1.41A(R)
R= 2.13 ohm

this is where i got stuck...

2.13 ohm= (1/3.3 ohm + 1/x ohm)^-1

how do i go about finding x...

the answer is 6 ohm but I am curious how. :D ty

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Mar 25, 2009

Bryster77

nevermind i got it

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