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प्रश्न
The circuit diagram given below shows the combination of three resistors R1, R2 and R3:
Find :
(i) total resistance of the circuit.
(ii) total current flowing in the circuit.
(iii) the potential difference across R1.
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उत्तर
(i) As shown in the figure, the resistors R2 and R3 are connected in parallel. Their total resistance is given by:
1/R = 1/R2+ 1/R3
Here, R2 = 3 Ω
R3 = 6 Ω
So,
1/R = 1/3 + 1/6
Or 1/R = (2+1)/6
1/R = 3/6
R = 2 Ω
This resistance is in series with the resistor, R1.
Total resistance = 2 Ω + R1
R1 = 4 Ω
Therefore, total resistance = 2 Ω + 4 Ω = 6 Ω
(ii) The current through the circuit can be calculated as follows:
Current, I = V / R
I = (12 / 6) A
I = 2 A
(iii) The potential difference across R1 = 2 A x 4 Ω = 8 V
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