Single Choice

The effective resistance of two resistor in parallel is $$\dfrac{12}{7}\Omega$$. If one of the resistors is disconnected the resistance becomes $$4\Omega$$. The resistance of the other resistor is

A$$4\Omega$$
B$$3\Omega$$
Correct Answer
C$$\dfrac{12}{7}\Omega$$
D$$\dfrac{7}{12}\Omega$$

Solution

For parallel resistance connection , we know that
$$\dfrac{1}{R_{eq}} = \dfrac{1}{R_{1}} + \dfrac{1}{R_{2}} $$
$$\dfrac {7}{12}=\dfrac {1}{4}+\dfrac {1}{R}\Rightarrow R=3\Omega$$

SIMILAR QUESTIONS

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