A parallel combination of 3ohms and 4ohms resistor is connected in series with a resistor of 4ohms and a battery of negligible resistance. Calculate the effective resistance in the circuit

Explanation:

Equivalent resistance of parallel combination of two resistors of 3 ohms and 4 ohms .

R₁ = 3 x 4 / ( 3 + 4 )

= 12 / 7 = 1.7 ohms .

This equivalent resistance is connected with 4 ohms in series

Total resistance = 1.7 ohms + 4 ohms

= 5.7 ohms.

Hence effective resistance of the circuit = 5.7 ohms .

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