Q18 of 19 Page 12

Study the following circuit and answer the following questions.


i. State the type of combination of the two resistors in the circuit.


ii. How much current is flowing through (a) 10 Ω register?


iii. What is the ammeter reading? ( CBSE 2011)

i. The two resistors are in the parallel combination because different amount of current flows through each resistor and each resistor has the same potential difference.


ii. Since the potential difference remains the same in the parallel combination


∴ V = 3 V


R = 10 Ω


By Ohm’s law



Current through 10 Ω resistance is 0.3 A


iii. Current for 15 Ω resistor is



Reading of Ammeter = Sum of current through 10 Ω and 15 Ω resistor = 0.3 A + 0.2 A = 0.5 A


Ammeter reading is 0.5 A

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